We explore the role of female directors in mitigating CEO luck. CEOs are ‘lucky’ when they receive stock option grants on days when the stock price is the lowest in the month of the grant, implying opportunistic timing. Our results show that board gender diversity significantly deters the opportunistic timing of option grants. The effect of board gender diversity is 17.19 percent stronger than that of board independence in reducing CEO luck. Board gender diversity plays an effective governance role, even more effective than board independence does. Our results support the benefits of board gender diversity in mitigating the agency cost.