UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of The

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported)

September 24, 2013

APPROACH RESOURCES INC.

(Exact name of registrant as specified in its charter)

Delaware |  | 001-33801 |  | 51-0424817
(State or other jurisdiction of incorporation) |  | (Commission File Number) |  | (IRS Employer Identification No.)
One Ridgmar Centre 6500 West Freeway, Suite 800 Fort Worth, Texas |  | 76116
(Address of principal executive offices) |  | (Zip Code)

(817) 989-9000

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨ | Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ | Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ | Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ | Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01 | Regulation FD Disclosure.

On September 24, 2013, Approach Resources Inc. (the “Company”) posted a new presentation titled “Investor Presentation, September 2013” under the “Investor Relations – Presentations” section of the Company’s website, www.approachresources.com.

For the benefit of all investors, the presentation is attached hereto as Exhibit 99.1.

Item 9.01 | Financial Statements and Exhibits.

(d) | Exhibits.

Exhibit No. |  | Description
99.1 |  | Investor Presentation, September 2013

In accordance with General Instruction B.2 of Form 8-K, the information in this current report on Form 8-K, including the attached exhibit, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any registration statement or other filing under the Securities Act of 1933, as amended, or the Exchange Act, except as otherwise expressly stated in such filing.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

APPROACH RESOURCES INC.
By: |  | /s/ J. Curtis Henderson
|  | J. Curtis Henderson Executive Vice President and General Counsel

Date: September 24, 2013

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EXHIBIT INDEX

Exhibit No. |  | Description
99.1 |  | Investor Presentation, September 2013

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