NexGen Commences Drilling at Radio Project, Eastern Athabasca Basin, Saskatchewan

June 20, 2013

NexGen Energy Ltd. (TSX.V:NXE) ("NexGen" or the "Company") is pleased to announce that it has commenced a 4,000 meter drill program at the Radio property, which is immediately adjacent to, and on trend approximately 2km east from, Rio Tinto's Roughrider uranium deposit. Rio Tinto purchased Hathor Exploration Ltd. and the Roughrider deposit for $650M in February 2012.

Previous detailed geophysical surveys of the Radio property have included aerial VTEM and magnetics, ground gravity and DC resistivity. Interpretation of this data has indicated a number of anomalous features on the property.

This initial diamond drilling program is designed to test coincident interpreted anomalies along strike from the Roughrider deposits along the interpreted shear zone towards the centre of the property. Drilling is expected to continue through to late July depending on ground conditions. See Figure 1.
NXE Total Field Magnetic Data Compilation
Figure 1: Radio Project -- Principal Target Areas

Depth to the basement is estimated at 170 to 200 metres while magnetic data interpretation shows a number of basement structural zones trending east-west, east-northeast and northeast, these being similar to those hosting mineralization on adjacent properties and in the area. Uranium in lake sediments showed elevated values (to 2.5x background) on most of the property.

The Radio Project has never been drill tested.

Leigh Curyer, NexGen's CEO commented "This is a very exciting milestone for the Company. The Radio Project, which was the cornerstone asset for the formation of NexGen, is a highly prospective target due to its structural setting and proximity to several high grade -- high tonnage world class uranium deposits. We are pleased to be drilling Radio, the first of two NexGen projects for this summer, three weeks ahead of schedule. Our other project is Rook 1, which is immediately adjacent to the North East of the Patterson Lake South (PLS) uranium discoveries, owned 50/50 by Fission Uranium Corp. and Alpha Minerals Inc. At Rook 1, the Company will shortly commence a DC resistivity survey in the southern section of Rook 1 adjacent to and along strike from PLS. This survey will assist the drill hole targeting for a 1500 metre diamond drilling campaign planned to commence in August."

Qualified Person

Andrew Browne, FAusIMM(CP), NexGen's Vice President, Exploration & Development, is a "qualified person" for the purposes of National Instrument 43-101 -- Standards of Disclosure for Mineral Projects, and has reviewed and approved the contents of this news release.

About NexGen

NexGen is a British Columbia corporation with a focus on the acquisition, exploration and development of Canadian uranium projects. NexGen has a highly experienced team of exploration professionals with a track record in the discovery of unconformity-style uranium deposits in Canada.

NexGen owns a portfolio of highly prospective uranium exploration assets in the Athabasca Basin, Saskatchewan, Canada, including, an option to earn a 70% interest in the Radio Project, immediately adjacent to Rio Tinto's Roughrider Deposit and a 100% interest in Rook 1, immediately adjacent to the north east of Patterson Lake South.

Leigh Curyer,
Chief Executive Officer
NexGen Energy Ltd.

+61 409 679 104
NexGen Energy Ltd.

The TSXV has neither approved nor disapproved the contents of this press release. Neither the TSXV nor its Regulation Services Provider (as that term is defined in the policies of the TSXV) accepts responsibility for the adequacy or accuracy of this release.

Forward-Looking Information

This news release contains "forward-looking information" within the meaning of applicable Canadian securities laws. Generally, but not always, forward looking information is identifiable by the use of words such as "expects", "anticipates", "believes", "projects", "plans", "intends" and other similar words, or statements that an event "may", "will", "should", "could", or "might" occur or be achieved and other similar expressions. Examples of such forward-looking information include, among others, statements regarding: the completion of the exploration activities and the results thereof.

Forward-looking information is based on the then current expectations, beliefs, assumptions, estimates and forecasts about the Company's business and the industry and markets in which it operates. Such information is not a guarantee of future performance and undue reliance should not be placed on forward-looking information. Assumptions and factors underlying the Company's expectations regarding forward-looking information contained herein include, among others: that general business and economic conditions will not change in a material adverse manner; that financing will be available if and when needed on reasonable terms; that the Company's current exploration activities can be achieved and that its other corporate activities will proceed as expected; that third party contractors, equipment and supplies and governmental and other approvals required to conduct the Company's planned exploration activities will be available on reasonable terms and in a timely manner.

Although the assumptions made by the Company in providing forward looking information are considered reasonable by management at the time the forward-looking information is given, there can be no assurance that such assumptions will prove to be accurate. Forward-looking information also involves known and unknown risks and uncertainties and other factors, which may cause actual events or results in future periods to differ materially from any projections of future events or results expressed or implied by such forward-looking information, including, among others: risks related to the availability of financing on commercially reasonable terms; changes in the market; potential downturns in economic conditions; industry conditions; actual results of exploration activities being different than anticipated; changes in exploration programs based upon results of exploration; future prices of metal; availability of third party contractors; availability of equipment and supplies; failure of equipment to operate as anticipated; accidents, effects of weather and other natural phenomena and other risks associated with the mineral exploration industry; environmental risks; changes in laws and regulations; community relations; and delays in obtaining governmental or other approvals. There can be no assurance that forward-looking information will prove to be accurate, as actual results and future events could differ materially from those anticipated, estimated or intended. NexGen undertakes no obligation to update or reissue forward-looking information as a result of new information or events except as required by applicable securities laws. The reader is cautioned not to place undue reliance on forward-looking information.