This study analyzed the impact of executive stock option compensation on firm value. Both linear and nonlinear relationships between executive stock option compensation and firm value were examined, and whether these effects differ depending on the firm's ownership and governance structure was investigated. The empirical results showed that as the proportion of executive stock option compensation increases, firm value increases. A U-shaped nonlinear relationship between the proportion of executive stock option compensation and firm value was found to have greater explanatory power than a linear relationship. Additionally, for professionally managed firms, stock option compensation for executives was found to be more effective in enhancing firm value than for owner-managed firms.