This study tries to extend previous works on behavioral corporate finance by examining the interac-tion between investment cash flow sensitivity and various CEO characteristics in either the existenceor inexistence of managerial optimism. Using a Q-investment model and departing from a sample of 475 annual observations, our results highlight that CEO’s financial education, CEO’s ownership and theiroptimism bias can explain distortions in corporate investment policy since they affect investment cashflow’s relationship.