In this study, we investigated whether managerial ability is associated with a corporate’s investment efficiency by mitigating investment distortions including over-investment or under- investment. Management plays significant role to make fundamental decisions including investments from planning through taking responsibility, hence it is important to empirically examine the relation between managerial ability and investment efficiency. Following Demerjian et al.(2012), we measured managerial ability based on DEA(Data Envelope Analysis) and tobit regression. In addition, the decrease in over or under-investment is defined as the improvement of investment efficiency following Biddle et al.(2009). Using listed firms in Korea during 2005-2014, the result shows that managerial ability is systematically positively associated with investment efficiency.