Golden Star (GSS) Announces Continued Drilling Success

DENVER, CO–(Marketwire – July 25, 2012) – Golden Star Resources Ltd. (NYSE MKT: GSS) (TSX: GSC) (GHANA: GSR)

– Intersects 59.4 meters grading 2.5 grams per tonne (g/t) gold beneath the current 242 reserve pit designs

– Intersects 25.2 meters grading 4.1 g/t gold and 20.6 meters grading 2.7 g/t gold beneath the currently operating Starter Pit

– Intersects 33.9 meters grading 2.2 g/t gold and 31.9 meters grading 1.8 g/t gold beneath the currently operating South East Pit

Golden Star Resources Ltd. (NYSE MKT: GSS) (TSX: GSC) (GHANA: GSR) (“Golden Star” or the “Company”) today provided an update on exploration activities at its Wassa mine in Ghana. Complete drill results, plans and sections are posted on the Company’s website at www.gsr.com or click the following link: http://www.gsr.com/Operations/Wassa.asp. (Note: All references to “widths” in this news release are to true widths unless otherwise indicated and all references to “m” are to meters.)

The exploration drilling at Wassa Main continued to intersect wider zones of over 2 g/t gold mineralization along strike and down dip. The current drilling program consists predominantly of step-out drilling testing the extents of the deeper mineralization below the current reserve pit designs. Preliminary in-house resource models and pit shells show that this mineralization could be economic should the grades and widths intersected thus far show good continuity. In order to accelerate the 50,000-meter drilling program now underway below the Wassa Main pit designs, the Company is augmenting its current drilling fleet of two owner-operated drill rigs with three additional contractor-operated multipurpose drilling rigs. The drilling contract has been awarded and the contractor has begun mobilizing equipment to site to commence drilling during August 1, 2012.

During the second quarter of 2012 a further 33 drill holes were completed totaling 8,040 meters. Drilling continued testing the B Shoot, Starter, South East and 242 areas at Wassa. Drilling results from the Starter area, which is the surface projection of the interpreted large scale fold hinge zone, have thus far been encouraging. These results include hole STDD018, which intersected 4.1 g/t gold over 25.2 meters at 15 meters below the current mining surface and within the current reserve pit. This hole also intersected another deeper zone (approximately 65 meters below the reserve pit design) of 2.7 g/t gold over 20.6 meters. Further drilling has been planned to follow up on this deeper zone both along strike and down dip. Significant results from the Starter (hinge zone) drilling during the second quarter of 2012 are summarized in the table below.

Starter Q2 2012 significant drill intersections

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                                                                   -
        Easting Northing Elev   Az    Dip   From   To   Drilled  True  Gold
Hole ID   (m)      (m)    (m) (deg.) (deg.)  (m)   (m)   Width  Width Grade
                                                           (m)    (m)   g/t
============================================================================
STDD015  39977    20251   961    90     -49   19.0  25.0   6.0    5.0   5.5
STDD016  39979    20225   961    90     -48   87.4 104.8   17.4   14.8  2.0
STDD016  39979    20225   961    90     -48  147.8 158.2   10.4   8.8   3.3
STDD018  40012    20375   958    90     -52  163.2 188.7   25.5   20.6  2.7
STDD018  40012    20375   958    90     -52   16.0  48.0   32.0   25.2  4.1
STDD019  40000    20332   957    90     -51  199.0 214.0   15.0   12.3  2.1
STDD019  40000    20332   957    90     -51  246.0 253.5   7.5    6.1   5.8
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Additional drilling was also conducted along the limbs of the Wassa Main fold targeting both B Shoot and South East deeper mineralization on the eastern limb. The South East drilling continued to intersect wider zones of gold mineralization, including BSDD124, which intersected South East mineralization at depth but was collared in the B Shoot pit, which drilled 33.9 meters true width grading 2.2 g/t gold. This intersection is approximately 50 meters below the deepest part of the current reserve pit designs and has confirmed previously announced (see the Company’s February 6, 2012, news release) mineralization intersected in SEDD039 (36.3 meters grading 5.4 g/t gold) and SEDD035 (20.9 meters grading 1.9 g/t gold), which are located approximately 60 meters up dip and 50 meters along strike from hole BSDD124, respectively. Significant results intersected at B shoot and South East during the second quarter are tabulated below.

B Shoot Q2 2012 significant drill intersections

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                                                                   -
        Easting Northing Elev   Az    Dip   From   To   Drilled  True  Gold
Hole ID   (m)      (m)    (m) (deg.) (deg.)  (m)   (m)   Width  Width Grade
                                                           (m)    (m)   g/t
============================================================================
BSDD124  40026    19825   983    90     -50   86.2  98.0   11.8   9.7   3.0
BSDD124  40026    19825   983    90     -50  239.5 280.9   41.4   33.9  2.2
BSDD124  40026    19825   983    90     -50  329.0 341.6   12.6   10.3  3.1
BSDD125  39757    20050  1015    90     -55  136.1 152.3   16.2   12.4  2.2
BSDD127  39854    20175   985    90     -59   80.4  88.8   8.4    6.0   12.3
BSDD127  39854    20175   985    90     -59  231.0 236.5   5.5    4.0   7.8
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South East Q2 2012 significant drill intersections

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                                                                   -
         Easting Northing Elev  Az     Dip    From   To  Drilled  True  Gold
 Hole ID   (m)      (m)    (m) (deg.) (deg.)  (m)   (m)   Width  Width Grade
                                                           (m)    (m)   g/t
============================================================================
SEDD050A  40071    19875  1009   90     -53  218.9 223.0   4.1    3.3   11.5
SEDD050A  40071    19875  1009   90     -53  237.2 252.9   15.7   12.5  2.7
 SEDD051  40052    19775  1008   90     -60  272.5 286.0   13.5   9.7   4.1
 SEDD052  40072    19850  1007   90     -55   48.0  53.0   5.0    3.9   10.6
SEDD057A  40331    19950  1001   90     -46   98.0 134.8   36.8   31.9  1.8
 SEDD058  40239    19951  1000   90     -55  161.7 166.7   5.0    3.9   21.3
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Limited drilling was conducted on the western limb of the fold along the 242 trend. The drilling tested the down dip extent of mineralization and defined the boundaries of a diorite body, which occupies the core of the fold. The diorite is a syn-volcanic intrusion, which provides rheological contrasts with the surrounding mafic volcanic flows, generating dilation zones where wide accumulations of gold mineralization occur. For example, hole 242DD054 intersected 59.4 meters grading 2.5 g/t gold. Where the mineralized structure intersects the diorite body, mineralization is often present but exhibits narrower zones and lower grade. Further drilling has been planned to test the extents of the diorite on both margins within the hinge zone to assist in delineating geometry of the mineralization. Significant drilling results in the 242 limb are outlined in the underlying table.

242 Pit Q2 2012 significant drill intersections

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                                                                   -
         Easting Northing Elev  Az     Dip    From   To  Drilled  True  Gold
 Hole ID   (m)      (m)    (m) (deg.) (deg.)  (m)   (m)   Width  Width Grade
                                                           (m)    (m)   g/t
============================================================================
242DD051  39912    20236   970   325    -70   73.2  78.0   4.8    4.4   5.9
242DD052  40019    20347   958   325    -75   54.0  67.0   13.0   11.4  2.3
242DD054  39756    20067  1000   325    -58  156.3 217.0   60.7   59.4  2.5
----------------------------------------------------------------------------

With the addition of the three contractor-operated drilling rigs to complete Phases 1 and 2 of the program, Golden Star expects to spend approximately $10.4 million over the next nine months, and drilling results will be used to update resource models and pit optimizations. Pending positive results of this program, further infill drilling campaigns in 2013 will be required to increase confidence in the classification of the resources and to enable possible conversion to reserves. Drilling results for the first half of 2012 are being incorporated into an updated resource estimate for the year-end resources and reserves statements.

Mitchel Wasel, Vice President of Exploration, commented, “The commitment from the Board to expand the drilling program at the Wassa Main deposits will enable Golden Star to make informed decisions on possible expansion scenarios over the next 18 months. Recent drilling results, which indicate that Wassa mineralization at depth is wider and higher grade than what has been mined to date, clearly support the Company’s plans to move forward aggressively with this drilling program.”

COMPANY PROFILE

Golden Star Resources holds the largest land package in one of the world’s largest and most prolific gold producing regions. The Company holds a 90% equity interest in Golden Star (Bogoso/Prestea) Limited and Golden Star (Wassa) Limited, which respectively own the Bogoso/Prestea and Wassa/HBB open-pit gold mines in Ghana, West Africa. In addition, Golden Star has an 81% interest in the currently inactive Prestea Underground mine in Ghana, as well as gold exploration interests elsewhere in Ghana, in other parts of West Africa and in Brazil in South America. Golden Star has approximately 259 million shares outstanding. Additional information is available at www.gsr.com.

Statements Regarding Forward-Looking Information: Some statements contained in this news release are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and other applicable securities laws. Such statements include: our expectations regarding our planned drilling and exploration activities for the remainder of 2012 and the timing thereof; the impact of our results of exploration on our reserves and resources and on the Wassa pit and Wassa operations; the potential for infill drilling campaigns in 2013; the timing of commencement of contract drilling; plans to spend approximately $10.4 million over the next nine months; and the timing of decisions with respect to expansion plans. Investors are cautioned that forward-looking statements are inherently uncertain and involve risks and uncertainties. Factors that could cause actual results to differ materially include timing of and unexpected events during exploration; variations in ore grade; variations in relative amounts of refractory, non-refractory and transition ores; technical or permitting issues, and fluctuations in gold price and costs. There can be no assurance that future developments affecting the Company will be those anticipated by management. Please refer to the discussion of these and other factors in our Form 10-K for 2011 and subsequent Forms 10-Q for 2012 and other filings of the Company with the United States Securities and Exchange Commission and the applicable Canadian securities regulatory authorities. The forecasts contained in this press release constitute management’s current estimates, as of the date of this press release, with respect to the matters covered thereby. We expect that these estimates will change as new information is received. While we may elect to update these estimates at any time, we do not undertake to update any estimate at any particular time or in response to any particular event.

QA/QC:

The technical contents of this press release have been reviewed by S. Mitchel Wasel, BSc Geology, a Qualified Person pursuant to National Instrument 43-101. Mr. Wasel is Vice President of Exploration for Golden Star and an active member and Registered Chartered Professional of the Australasian Institute of Mining and Metallurgy.

The results for Wassa quoted herein are based on the analysis of saw-split HQ/NQ diamond half core or a three kilogram single stage riffle split of a nominal 25 to 30 kg Reverse Circulation chip sample which has been sampled over nominal one meter intervals (adjusted where necessary for mineralized structures). Sample preparation and analyses have been carried out at SGS Laboratories in Tarkwa using a 1,000 gram slurry of sample and tap water which is prepared and subjected to an accelerated cyanide leach (LEACHWELL). The sample is then rolled for twelve hours before being allowed to settle. An aliquot of solution is then taken, gold extracted into Di-iso Butyl Keytone (DiBK), and determined by flame Atomic Absorption Spectrophotometry (AAS). Detection Limit is 0.01ppm.

All analytical work is subject to a systematic and rigorous Quality Assurance-Quality Control (QA-QC). At least 5% of samples are certified standards and the accuracy of the analysis is confirmed to be acceptable from comparison of the recommended and actual “standards” results. The remaining half core is stored on site for future inspection and detailed logging, to provide valuable information on mineralogy, structure, alteration patterns and the controls on gold mineralization.

Additional information on earlier drilling results at Wassa are available in our February 6, 2012, press release.