Abstract: This paper estimates innovation efficiency of China's listed companies by constructing the heteroscedastic stochastic frontier model, and analyzes the impact of agency conflict on efficiency. The results show that: (1) the innovation efficiency of China's listed companies declines by 25%-45% due to agency conflicts; (2) Improvement of equity concentration and balance degree and implementation of executive incentive policy will significantly reduce the level of agency conflicts, and enhance investment in innovation; institutional ownership is not a key factor of technological innovation;(3) Innovation efficiency of state-controlled companies shows a steadily increasing trend and gradually higher than the non-state-owned listed companies during the sample period.

Key words: innovation efficiency, innovation constraints, agency conflicts, stochastic frontier model