As filed with the Securities and Exchange Commission on June 16, 2014

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ENERJEX RESOURCES, INC.

(Exact name of registrant as specified in its charter)

4040 Broadway, Suite 508

San Antonio, TX 78209

Telephone: (210) 451-5545

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive
offices)

National Corporate Research, Ltd.

202 South Minnesota Street

Carson City, NV 89703

Telephone: (888) 600-9540

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate Date of Commencement of Proposed Sale to the Public: From time to time after the date this registration statement is declared effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box:  ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:   x 333-193976

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

CALCULATION OF REGISTRATION FEE

This Registration Statement shall become effective upon filing with the Securities and Exchange Commission in accordance with Rule 462(b) promulgated under the Securities Act.

EXPLANATORY NOTE AND INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

This Registration Statement is being filed with the Securities and Exchange Commission (the “Commission”) pursuant to Rule 462(b) under the Securities Act of 1933, as amended. This Registration Statement relates to the public offering of its Series A Cumulative Redeemable Perpetual Preferred Stock, par value $0.001 per share contemplated by the Registration Statement on Form S-1, as amended (File No. 333-193976), initially filed with the Commission by the Registrant on February 14, 2014 (as amended, the “Prior Registration Statement”), and is being filed for the sole purpose of registering additional securities of the same class as were included in the Prior Registration Statement. This Registration Statement includes the registration statement facing page, this page, the signature page, an exhibit index, an opinion of counsel regarding the legality of the securities being registered and a related consent, and the consent of an independent registered public accounting firm and independent petroleum engineer. The contents of the Prior Registration Statement including the power of attorney and all exhibits thereto are hereby incorporated by reference.

The required opinions and consents are listed on an Exhibit Index attached hereto and filed herewith.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Antonio, State of Texas on June 16, 2014.

POWER OF ATTORNEY

Pursuant to the requirements of the Securities Act of 1933, as amended this registration statement has been signed by the following persons in the capacities indicated, on June 16, 2014.

INDEX TO EXHIBITS

* Incorporated by reference from the Company’s Registration Statement on Form S-1, as amended (File No. 333-193976), initially filed by the Company on June 4, 2014 and declared effective by the Securities and Exchange Commission on June 16, 2014.