First Mining Signs Option Agreement FOR Its Las Margaritas GOLD Property IN Durango, Mexico

FF: TSX

FFMGF: OTCQX

FMG: FRANKFURT

FIRST MINING SIGNS OPTION AGREEMENT FOR ITS

LAS MARGARITAS GOLD PROPERTY IN DURANGO, MEXICO

August 2, 2018

VANCOUVER, BC, CANADA – First Mining Gold Corp. (“First Mining” or the “Company”)

is pleased to announce the signing of an option agreement with Gainey Capital Corp. (“Gainey”),

granting Gainey the right to earn a 100% interest in First Mining’s Las Margaritas Gold Property

(“Las Margaritas”) located in the State of Durango, Mexico.

The property is located approximately 140 kilometres to the southeast of Mazatlan, Sinaloa and

is comprised of two mineral concessions encompassing a total of 500 hectares. See Figure 1

further below.

Jeff Swinoga, President & CEO of First Mining stated, “This transaction unlocks the unrealized

value of this prospective but under-explored Mexican gold property. Since First Mining is focusing

on advancing the development of its Springpole Gold Project and Goldlund Gold Project, each

in northwestern Ontario , entering into this option agreement adds immediate value to our

shareholders while at the same time negating any holding costs on this property.”

Under the terms of the four year option agreement, Gainey can elect to make either annual share

or cash payments to First Mining in the following amounts:

Payment Term

CAD$ Aggregate Value of

Gainey Common Shares

(applicable Mexican VAT to

be paid in cash payment)

CAD$ Cash Payment

(inclusive of

applicable Mexican

VAT @ 16%)

Upon approval by the TSX Venture

Exchange (“TSX-V”)

$75,000 in Shares N/A $12,000 in Cash - VAT

First anniversary date of the

agreement

$175,000 in Shares $174,000 in Cash $28,000 in Cash - VAT

Second anniversary date of the

agreement

$250,000 in Shares $261,000 in Cash $40,000 in Cash - VAT

Third anniversary date of the

agreement

$225,000 in Shares $232,000 in Cash $36,000 in Cash - VAT

Fourth anniversary date of the

agreement

$225,000 in Shares $232,000 in Cash $36,000 in Cash - VAT

In addition, as per the terms of the option agreement, Gainey will make annual cash payments

to First Mining of USD$25,000 from September 2018 to September 2020, and USD$250,000 in

September 2021 in connection with an existing agreement on the property , and will incur

exploration expenditures on the Las Margaritas property totaling US D$1,000,000 over the four

year option period. Upon completion, Gainey will obtain 100% ownership of the Las Margaritas

property and First Mining will retain a 2% net smelter returns (“NSR”) royalty, with Gainey having

the right to buy back 1% of the NSR royalty for US D$1,000,000 up until the first anniversary of

the commencement of commercial production at the property.

Figure 1: Location of Las Margaritas Property in Durango State, Mexico

The transaction and the issuance of Gainey’s common shares pursuant to the option agreement

are subject to acceptance by the TSX Venture Exchange.

ABOUT FIRST MINING GOLD CORP.

First Mining Gold Corp. is an emerging development company with a diversified portfolio of gold

projects in North America. Having assembled a large resource base of 7 million ounces of

gold in the Measured and Indicated categories and 5 million ounces of gold in the Inferred

category in mining friendly jurisdictions of eastern Canada, First Mining is now focused on

advancing its assets towards production. The Company currently holds a portfolio of 25 mineral

assets in Canada, Mexico and the United States

For further information, please contact Jeff Swinoga, Presi dent and CEO, at 416 -816-0424, or

Derek Iwanaka, Vice President of Investor Relations, at 604- 639-8824, or visit our website

at www.firstmininggold.com.

ON BEHALF OF FIRST MINING GOLD CORP.

“Keith Neumeyer”

Keith Neumeyer

Chairman

Cautionary Note Regarding Forward-Looking Statements

This news release includes certain "forward- looking information” and "forward- looking

statements” (collectively "forward -looking statements”) within the meaning of applicable

Canadian and United States securities legislation including the United States Private Securities

Litigation Reform Act of 1995. These forward-looking statements are made as of the date of this

news release. Forward-looking statements are frequently, but not always, identified by words

such as "expects”, "anticipates”, "believes”, “plans”, “projects”, "intends”, "estimates”,

“envisages”, "potential”, "possible”, “strategy”, “goals”, “objectives”, or variations thereof or

stating that certain actions, events o r results "may", "could", "would", "might" or "will" be taken,

occur or be achieved, or the negative of any of these terms and similar expressions.

Forward-looking statements in this news release relate to future events or future performance

and reflect cu rrent estimates, predictions, expectations or beliefs regarding future events and

include, but are not limited to, statements with respect to: (i) the consideration payable by Gainey

to First Mining under the terms of the option agreement between the two c ompanies; (ii) the

annual cash payments that Gainey is required to make to First Mining between September 2018

and September 2021; (iii) the exploration expenditures that Gainey is required to incur on the

Las Margaritas property during the four year option period; (iv) the commencement of

commercial production at the Las Margaritas property; and (v) TSX -V approval. All forward-

looking statements are based on First Mining's or its consultants' current beliefs as well as

various assumptions made by them and information currently available to them. There can be

no assurance that such statements will prove to be accurate, and actual results and future events

could differ materially from those anticipated in such statements. Forward-looking statements

reflect the beliefs, opinions and projections on the date the statements are made and are based

upon a number of assumptions and estimates that, while considered reasonable by the

respective parties, are inherently subject to significant business, economic, competitive, political

and social uncertainties and contingencies. Many factors, both known and unknown, could

cause actual results, performance or achievements to be materially different from the results,

performance or achievements that are or may be expressed or implied by such forward-looking

statements and the parties have made assumptions and estimates based on or related to many

of these factors. Such factors include, without limitation; fluctuations in the spot and forward

price of gold, silver, base m etals or certain other commodities; fluctuations in the currency

markets (such as the Canadian dollar versus the U.S. dollar); changes in national and local

government, legislation, taxation, controls, regulations and political or economic developments;

risks and hazards associated with the business of mineral exploration, development and mining

(including environmental hazards, industrial accidents, unusual or unexpected formations,

pressures, cave -ins and flooding); the presence of laws and regulations that may impose

restrictions on mining; employee relations; relationships with and claims by local communities,

indigenous populations and other stakeholders; availability and increasing costs associated with

mining inputs and labour; the speculative nature of mineral exploration and development; title to

properties.; and the additional risks described in the Company’s Annual Information Form for the

year ended December 31, 2017 filed with the Canadian securities regulatory authorities under

the Company’s SEDAR profile at www.sedar.com, and in the Company’s Annual Report on Form

40-F filed with the SEC on EDGAR.

Cautionary Note to United States Investors

This news release has been prepared in accordance with the requirements of the securities laws

in effect in Canada, which differ from the requirements of U.S. securities laws. Unless otherwise

indicated, all resource and reserve estimates included in this news release have been prepared

in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI

43-101”) and the Canadian Institute of Mining, Metallurgy, and Petroleum 2014 Definition

Standards on Mineral Resources and Mineral Reserves. NI 43-101 is a rule developed by the

Canadian Securities Administrators which establishes standards for all public disclosure an

issuer makes of scientific and technical information concerning mineral projects. Canadian

standards, including NI 43- 101, differ significantly from the requirements of the United States

Securities and Exchange Commission ("SEC”), and mineral resource and reserve information

contained herein may not be comparable to similar information disclosed by U.S. companies. In

particular, and without limiting the generality of the foregoing, the term "resource” does not

equate to the term "reserves”. Under U.S. standards, mineralization may not be classified as a

"reserve” unless the determination has been made that the mineralization could be economically

and legally produced or extracted at the time the reserve determination is made. The SEC's

disclosure standards normally do not permit the inclusion of information concerning "measured

mineral resources”, "indicated mineral resources” or "inferred mineral resources” or other

descriptions of the amount of mineralization in mineral deposits that do not constitute "reserves”

by U.S. standards in documents filed with the SEC. Investors are cautioned not to assume that

any part or all of mineral deposits in these categories will ever be converted into reserves. U.S.

investors should also understand that "inferred mineral resources” have a great amount of

uncertainty as to their existence and great uncertainty as to their economic and legal feasibility. It

cannot be assumed that all or any part of an "inferred mineral resource” will ever be upgraded to

a higher category. Under Canadian rules, estimated "inferred mineral resources” may not form

the basis of feasibility or pre-feasibility studies except in rare cases. Investors are cautioned not

to assume that all or any part of an "inferred mineral resource” exists or is economically or legally

m

ineable. Disclosure of "contained ounces” in a resource is permitted disclosure under

Canadian regulations; however, the SEC normally only permits issuers to report mineralization

that does not constitute "reserves” by SEC standards as in- place tonnage and grade without

reference to unit measures. The requirements of NI 43 -101 for identification of "reserves” are

also not the same as those of the SEC, and reserves reported by the Company in compliance

with NI 43- 101 may not qualify as "reserves” under SEC standards. Accordingly, information

concerning mineral deposits set forth herein may not be comparable with information made

public by companies that report in accordance with U.S. standards.