Exhibit 31.2

CERTIFICATION

I, William D. Waddill, certify that;

1. I have reviewed this Form 10-K/A of Calithera Biosciences, Inc.; 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.

Date: November 12, 2015	/s/ William D. Waddill
	William D. Waddill Senior Vice President, Chief Financial Officer, Treasurer and Secretary (Principal Financial and Accounting Officer)