Using data from 43 countries for the period 1993-2012, this paper investigates whether investor education increases the earnings quality, which has not been explored yet. I measure earnings quality in three aspects: the signed abnormal accruals, the loss avoidance, and the earnings conservatism. I argue that educated investors require high quality earnings. Consistent with my conjecture, the empirical results show that in countries with higher investor education level, firms tend to report earnings with lower signed abnormal accruals, higher likelihood of reporting losses, and faster losses recognition compared with gains. In sum, the investor education is positively associated with the earnings quality in different institution environments. Furthermore, the positive effect of investor education on earnings quality only exists in countries with strong investor legal protection, suggesting a complementary role of education in corporate governance. My study also provides implications for policy makers that investor education could be one effective way to regulate reported earnings.