This study is the first to explore the effect of the global financial crisis (GFC) on the relationship between directors and officers (D&O) insurance and investment efficiency. The empirical results show that D&O insurance did not have a significant impact on the level of overinvestment during or after the GFC, nor did D&O insurance have a significant impact on the level of underinvestment during the GFC. However, D&O insurance significantly mitigated underinvestment after the GFC. These findings have valuable implications for policymakers, corporations, and investors in terms of promoting D&O insurance policies, seeking investment efficiency, and making informed decisions.