As participants and executors of internal control, company staff have a deep understanding of the internal control of the company. If they find that there exists a false disclosure in the internal control, whether the company staff play the role of “whistleblower” and expose such a fraud will directly influence the behavior of the company and the audit. This paper establishes a single phase of incomplete information game models to analyze the conflict of interest among the staff, the company and the auditor. The results show that a good protection system of whistleblowers can increase the staff s willingness to blow his whistle, reduce the cost of external audit, as well as prevent the false disclosure of the company.