Vancouver, BC, February 17th, 2015 -- NexGen Energy Ltd. (TSX-V: NXE) ("NexGen" or the "Company") is pleased to announce ongoing results from our winter 2015 drilling program from our 100% owned Rook I property, Athabasca Basin, Saskatchewan. Further angled drill testing in two holes along strike to the southwest of high-grade mineralization in AR-14-30 (46.0 m of 10.32% from 520.0 m depth) have encountered significant dense accumulations of semi-massive to massive pitchblende mineralization with associated off-scale radioactivity from >10,000 to 60,000 cps.

Highlights:

Arrow Zone

• Angled drill hole AR-15-37 intersected 76.0 m total composite mineralization including 9.35 m off-scale radioactivity (>10,000) within a 264.5 m section (405.0 to 669.5 m);
• Angled drill hole AR-15-38 intersected 82.35 m total composite mineralization including 4.5 m off-scale radioactivity (>10,000 cps) within a 247.5 m section (474.0 to 721.5 m). AR-15-38 has successfully extended the intensive high grade mineralization intersected in AR-14-30 to 81 m southwest along strike (within the previously established 515 m strike length of the Arrow zone).

Radon Target (400 metres along strike to north east of Arrow)

• The 3rd rig has commenced drilling at this high priority area where a clustered radon anomaly, optimally situated along the southeast dipping VTEM conductor, is projected to reach the unconformity. (See Figure 4).

At Arrow, a total of 4,531.9 m have been drilled this winter as of February 8th, 2015. Drill hole locations are shown in Figure 1, and a long-section illustrating the mineralized intersections is shown in Figure 2. Drill hole details and scintillometer (handheld RS-120) results are summarized in Table 1.

Garrett Ainsworth, NexGen's Vice-President, Exploration and Development, commented "This significant 81 metre step-out to the southwest of AR-14-30 into continuous high-grade mineralization with AR-15-38 represents a substantial step towards successfully executing our goal of building a significant resource at Arrow efficiently."

Leigh Curyer, Chief Executive Officer commented, "The strategy of aggressive step-out drilling has delivered yet again, significantly expanding this particular high-grade zone of Arrow. The technical team continues to demonstrate its understanding and confidence in the mineralized system at Arrow with close to a 100% hit rate. The commencement of drilling the radon-in-water anomalies, 400 meters along strike to the north east of Arrow and in parallel to the development of Arrow is very exciting for the Company and its shareholders."
Maximum internal dilution 2.00 m downhole

• All depths and intervals are meters downhole
• "Anomalous" means >500 cps (counts per second) total count gamma readings by gamma scintillometer type RS-120
• "Off-scale" means >10,000 cps (counts per second) total count gamma readings by gamma scintillometer type RS-120
• Where "Min cps" is <500 cps, this refers to local low radiometric zones within the overall radioactive interval

Natural gamma radiation in drill core reported in this news release was measured in counts per second (cps) using a Radiation Solutions Inc. RS-120 gamma-ray scintillometer. The reader is cautioned that total count gamma readings may not be directly or uniformly related to uranium grades of the rock sample measured; they should be used only as a preliminary indication of the presence of radioactive minerals. All intersections are downhole. Core interval measurements and true thicknesses are yet to be determined.

Split core samples will be taken systematically, and intervals will be submitted to SRC Geoanalytical Laboratories (an SCC ISO/IEC 17025: 2005 Accredited Facility) of Saskatoon for analysis. All samples sent to SRC will be analyzed using ICP-MS for trace elements on the partial and total digestions, ICP-OES for major and minor elements on the total digestion, and fusion solution of boron by ICP-OES. Mineralized samples are analyzed for U3O8 by ICP-OES and select samples for gold by fire assay. Assay results will be released when received.

ARROW ZONE DRILLING

AR-15-37:

Hole AR-15-37 was drilled as an angled "scissor" hole designed to test the down-plunge projection of high-grade uranium mineralization discovered in hole AR-14-30 (10.32% U3O8 over 46.0 m). The hole intersected bleached and hematized Athabasca Group sandstone between 114.0 m and the unconformity at 129.8 m. Basement lithologies consisted largely of intermediate to mafic intrusives, semipelitic gneiss to granofel, and locally graphitic pelitic gneiss and mylonites. A total composite mineralization of 76.0 m including 9.35 m of off-scale radioactivity (>10,000 cps) was intersected in at least three horizons within a 264.5 m section (405.0 to 669.5 m). Mineralization consisted of locally semi-massive to massive veins, pods, fracture controlled, foliation controlled and disseminated pitchblende. The hole was terminated at a depth of 759.0 m and represents an interpreted 50 m down-plunge step-out to high-grade uranium mineralization intersected in AR-14-30.

AR-15-38:

Hole AR-14-38 was drilled as an angled 50 m southwest step-out from hole AR-15-34b (10.3m of off-scale radioactivity; assays pending). The hole intersected bleached Athabasca Group sandstone between 120.0 m and the unconformity at 127.0 m. Basement lithologies consisted largely of intermediate to mafic intrusives, semipelitic gneiss to granofel, and locally graphitic pelitic gneiss and mylonites. A total composite mineralization of 82.35 m including 4.5 m of off-scale radioactivity (>10,000cps) was intersected in at least three horizons within a 247.5 m section (474.0 to 721.5 m). Mineralization consisted of semi-massive to massive veins, pods, fracture controlled, foliation controlled and disseminated pitchblende. The hole was terminated at a depth of 783.0 m. It successfully defined uranium mineralization that remains open in all directions and is 81 m southwest from intensive high-grade mineralization intersected in AR-14-30 (46.0 m of 10.32% from 520.0 m). This 81 m step out is on the A2 high-grade mineralized shear zone, which is within the previously established 515 m strike length of the Arrow zone.

FURY AREA DRILLING

Six regional drill holes (RK-14-46 and -51) in 1356.5 m have been drilled at the Fury area within the Rook I property, which is also reported in this news release. Drill hole locations are show in Figure 3.

Hole RK-15-46 was the first drill hole collared at the Fury Target Area located approximately 13.5 km southeast of the Arrow Zone. The target area is interpreted as an eastern splay from the Derkson conductor corridor which is known to host anomalous uranium concentrations on the Rook I property discovered by past operators (in 1978 DER-04 intersected 0.2% U over 2.5 m).

Hole RK-15-46, -47 and -48 were all collared with an azimuth of 090° (east) and dip of -60° to test prominent VTEM conductor breaks and coincident gravity gradient shifts. Overburden thickness ranged from 33.0 to 43.7 m. No Athabasca Group sandstone was present, and basement lithologies included semipelitic and granodiorite gneiss hanging wall, a prospective graphitic and pyritic pelitic gneiss and mylonite unit with an apparent thickness ranging from 7.2 to 21.8 m, and a tonalite to granodiorite gneiss footwall. Weak to strong clay and chlorite alteration was intersected intermittently throughout these drill holes.

Drill hole RK-15-46 did not intersect any significant radioactivity. The down-hole gamma survey (2PGA-1000 probe) in RK-15-47 encountered a maximum peak of 931 cps (>500 cps is anomalous) at 170.0 m within the tonalite gneiss footwall rock, which was detected as a thoraniferous source with the handheld spectrometer (RS-125). In drill hole RK-15-48 a maximum peak of 831 cps was encountered at a depth of 183.4 m within the tonalite gneiss footwall rock, which was detected as a thoraniferous source.

Hole RK-15-49, -50 and -51 were all collared with an azimuth of 090° (east) and dip of -60° to test a VTEM conductor break and coincident gravity low trough. Overburden thickness ranged from 54.0 to 69.0 m. No Athabasca Group sandstone was present, and basement lithologies comprised an intercalated mess of granite gneiss, gabbro, granodiorite gneiss, pegmatite, and weakly graphitic pelitic and semipelitic gneiss. Weak to strong pervasive and mineral controlled clay alteration was intersected in all drill holes.

Drill holes RK-15-49 and -50 did not intersect any significant radioactivity. The down-hole gamma survey (2PGA-1000 probe) in RK-15-51 encountered a maximum peak of 803 cps (>500 cps is anomalous) at 157.9 m within granite gneiss, which was detected as a thoraniferous source with the handheld spectrometer (RS-125).