Digital transformation has become a new driving force for corporate development, widely embraced by managers. However, in the actual digital transformation process, some companies’ performances are characterized by “more talk, less action”. To measure the phenomenon, this paper innovatively constructs the Digital Disclosure Anomaly (DDA) indicator using Chinese A-share listed companies’ data from 2013 to 2021 and examines the impact of DDA on corporate innovation efficiency by Saying is Believing theory. We find that DDAs show a long-term negative impact on corporate innovation efficiency. Our mechanism analysis suggests that DDAs reduce innovation efficiency through resource misallocation, which is driven by two mechanisms: the manager squandering effect and the inefficient investment effect. Our results suggest that DDAs are harmful for corporate innovation efficiency by the Saying is Believing (SIB) effect and corporate DDA behavior is detrimental to sustainability in digital economy development.