Exhibit 31.1

CERTIFICATION

I, Brad Johnson, certify that:

1.I have reviewed this Amendment No. 2 to the Annual Report on Form 10-K of Ultra Petroleum Corp.; and

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report.