Taking the A share listed firms in China in 2007 2015 as an example, this paper analyzes the effects of firm strategy deviance from convention and internal control quality on financial statement comparability. The results show that: (1) deviance from conventional strategy has a negative effect on financial statement comparability, (2) internal control quality has a positive effect on financial statement comparability, and (3) internal control quality can neutralize the negative effect of firm strategy deviance on financial statement comparability. This conclusion is significantly meaningful for the promotion of firm’s strategy disclosure, enforcement of internal control and the judgement about financial reporting quality by the users.