IsoEnergy Intersects 7.5m of 14.5% U3O8 in Drill Hole LE20-51 Including 3.5m of 30.9% U3O8

VANCOUVER, March 31, 2020 - IsoEnergy Ltd. ("IsoEnergy" or the "Company") (TSXV: ISO; OTCQX: ISENF) is pleased to report additional assay results from the winter 2020 drilling program at the Hurricane zone.? The Hurricane zone is a new discovery of high-grade uranium mineralization on the Company's 100% owned Larocque East property (the "Property") in the Eastern Athabasca Basin of Saskatchewan (Figure 1).

Highlights:

• Assays received from drill hole LE20-51 average 14.5% U₃O₈ and 3.5% Ni over 7.5m from 322.5 to 330.0m (see the core photo in Figure 2)
• A higher-grade sub-interval within LE20-51 averages 30.9% U₃O₈ and 7.1% Ni over 3.5 m from 325.5 to 329.0m
• Other assay results include 3.6% U₃O₈ and 1.4% Ni over 10.0m from 318.0 to 328.0m in drill hole LE20-46.
• Assays from the final two drill holes LE20-52 and LE20-53 are still pending, both of which intersected long lengths of strong uranium mineralization, including sub-intervals of off-scale radioactivity (>65K CPS RS-125)

Craig Parry, Chief Executive Officer commented: "These results come at an important time for the uranium mining industry. With the suspension of operations at several uranium mines and mills around the world including at the world's largest mine - Cameco's Cigar Lake ? we are starting to see uranium prices in the spot market rise strongly in recent days. Should these mines stay offline for an extended period we see further upward pressure on prices as utilities move to secure supply. IsoEnergy continues to be one of the most active uranium explorers globally and the great results from these holes are further evidence of the high-grade nature and significance of the Hurricane discovery. We currently have $3.7 million on hand and so are well funded for 2020 and beyond."

Steve Blower, Vice President of Exploration commented: "Assay results from the Hurricane zone continue to impress.? Drill hole LE20-51 intersected a new zone of higher-grade uranium mineralization.? Previously reported radioactivity results in drill holes LE20-52 and LE20-53 suggest that those two drill holes are both within the same higher-grade zone and we look forward to reporting their assay results soon.? The large size of the 575m long Hurricane zone footprint combined with a relatively small number of drill holes completed to date suggests that there is good potential for the discovery of other higher-grade zones within Hurricane."

Assays Received

Drill Hole LE20-51 (Hurricane Section 4510E)

Drill hole LE20-51 was completed 8m south of previously reported drill hole LE20-32A (19.6% U₃O₈ over 8.5m) and was designed to evaluate the potential for additional high-grade mineralization south of that drill hole.? The result was successful, with LE20-51 intersecting a thick zone of strong uranium and nickel mineralization that averages 14.5% U₃O₈ and 3.5% Ni over 7.5m from 322.5 to 330.0m.? This includes a 3.5m subinterval from 325.5 to 329.0m that averages 30.9% U₃O₈ and 7.1% Ni.? The higher-grade subinterval contains common "worm-rock" textured intergrowths of pitchblende and hematite along with abundant visible nickel mineralization (Figure 2).? Figures 3 and 4 show the position of the drill hole on a plan-view and cross-section, respectively.?

Drill Holes LE20-46 and LE20-48 (Hurricane Section 4485E)

Drill holes LE20-46 and 48 were designed to evaluate the potential for additional high-grade uranium mineralization to the north and south of drill hole LE19-12 (Figures 3 and 5).? Both of the drill holes intersected thick intervals of uranium mineralization.? Drill hole LE20-46 intersected 3.6% U₃O₈ and 1.4% Ni over 10.0m from 318.0 to 328.0m, including 2.0m that averages 12.8% U₃O₈ and 1.6% Ni from 323.0 to 325.0m.? Drill hole LE20-48 intersected 1.3% U₃O₈ over 11.5m from 316.0 to 327.5m.

Drill Hole LE20-49 (Hurricane Section 4510E)

Completed 15m north of drill hole LE20-32A, drill hole LE20-49 intersected a long interval of uranium mineralization that averages 1.1% U₃O₈ over 9.0m from 320.5 to 329.5m.

Next Steps

Assays for the final two drill holes completed at the Hurricane zone are expected to be reported soon.? Data compilation and interpretation of the winter drilling results are well underway, as is planning for a potential summer drilling program that will continue to define the extent of the Hurricane zone.

The Larocque East Property and the Hurricane Zone

The 100% owned Larocque East property consists of 20 mineral claims totaling 8,371 ha that are not encumbered by any royalties or other interests.? Larocque East is immediately adjacent to the north end of IsoEnergy's Geiger property and is 35 km northwest of Orano Canada's McClean Lake uranium mine and mill.?

Along with other target areas, the Property covers a 15-kilometre-long northeast extension of the Larocque Lake conductor system; a trend of graphitic metasedimentary basement rocks that is associated with significant uranium mineralization at the Hurricane zone, and in several occurrences on Cameco Corp. and Orano Canada Inc.'s neighbouring property to the southwest of Larocque East.? The Hurricane zone was discovered in July, 2018 and was followed up with 29 drill holes in 2019 and an additional 14 drill holes to date in 2020.? Dimensions are currently 575m along-strike, 40m wide and up to 11m thick.? The zone is open for expansion along-strike to the east and on most sections.? Mineralization is polymetallic and commonly straddles the sub-Athabasca unconformity 320 m below surface.? The best intersection to date is 33.9% U₃O₈ over 8.5m in drill hole LE20-34.? Drilling at Cameco Corp.'s Larocque Lake zone on the neighbouring property to the southwest has returned historical intersections of up to 29.9% U₃O₈ over 7.0m in drill hole Q22-040.? Like the nearby Geiger property, Larocque East is located adjacent to the Wollaston-Mudjatik transition zone - a major crustal suture related to most of the uranium deposits in the eastern Athabasca Basin.? Importantly, the sandstone cover on the Property is thin, ranging between 140m and 330m in previous drilling.?

Table 1 ? 2020 Hurricane Zone Results

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Qualified Person Statement

The scientific and technical information contained in this news release was prepared by Andy Carmichael, P.Geo., IsoEnergy's Senior Geologist, who is a "Qualified Person" (as defined in NI 43-101 ? Standards of Disclosure for Mineral Projects).? Mr. Carmichael has verified the data disclosed. ?All radioactivity measurements reported herein are total gamma from an RS-125 hand-held spectrometer.? As mineralized drill holes at the Hurricane zone are oriented very steeply (-80 to -90 degrees) into a zone of mineralization that is interpreted to be horizontal, the true thickness of the intersections is expected to be greater than or equal to 90% of the core lengths.? This news release refers to properties other than those in which the Company has an interest. ?Mineralization on those other properties is not necessarily indicative of mineralization on the Company's properties. ?All chemical analyses are completed for the Company by SRC Geoanalytical Laboratories in Saskatoon, SK.? For additional information regarding the Company's Larocque East Project, including its quality assurance and quality control procedures, please see the Technical Report dated effective May 15, 2019 on the Company's profile at www.sedar.com.

About IsoEnergy

IsoEnergy is a well-funded uranium exploration and development company with a portfolio of prospective projects in the eastern Athabasca Basin in Saskatchewan, Canada. ?The Company recently discovered the high-grade Hurricane Zone of uranium mineralization on its 100% owned Larocque East property in the Eastern Athabasca Basin.? IsoEnergy is led by a Board and Management team with a track record of success in uranium exploration, development and operations. ?The Company was founded and is supported by the team at its major shareholder, NexGen Energy Ltd.??

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Forward-Looking Information

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SOURCE IsoEnergy Ltd.