Mutual Fund is one of the most important mechanisms for indirect investment in financial markets, which provides better conditions in terms of risk and return, especially for amateur investors. This research examined the effects of mutual fund managers' characteristics on the performance of Iranian mutual funds. The research was carried out on all Iranian mutual funds during 2007 to 2011. Generalized Lease Square (GLS) was employed to examine these effects. The results show that fund manager's Age, MBA, Gender, and Tenure significantly influence fund performance.