Carrizo Oil & Gas (CRZO) 8-K Carrizo Oil & Gas Announces Delaware Basin Acquisition and Provides Operational Update

Exhibit 23.1

Consent of Independent Auditors

We consent to the incorporation by reference in the registration statement (No.333-198459) on FormS-3ASR and the registration statements (Nos.333-218036,333-196252,333-181585,333-162888,333-137273,333-116528,333-55838, and333-35245) onForm S-8 of Carrizo Oil & Gas, Inc. of our report dated June 28, 2017, with respect to the combined statement of revenues and direct operating expenses of oil and gas properties to be acquired by Carrizo Oil & Gas, Inc. for the year ended December 31, 2016, which report appears in the Form8-K of Carrizo Oil & Gas, Inc. to be filed on June 28, 2017.

/s/ JOHNSON, MILLER & CO., CPA’S PC

Midland, Texas

June 28, 2017