关键词: 市场竞争, 劳动收入份额, 反垄断法

Abstract: In the context of China's implementation of making solid advances toward common prosperity and strengthening antitrust enforcement，this paper uses the enactment of the Antitrust Law as a unique shock to examine empirically the impact of market fair competition on labor income share The result shows that compared with competitive firms，the labor income share of monopoly firms increases significantly after the enforcement of the Antitrust Law The positive relation between the Antitrust Law and labor income share is amplified in high executive monopoly regions，hightech industries，and firms with higher ratio of scientists and engineers，and is dampened in firms facing lower agency cost Further，this paper finds that reducing the monopoly rent and improving R&D intensity are important channels through which the Antitrust Law increases labor income share；the Antitrust Law increases the labor income share of staff，and decreases the labor income share of managers

Key words: market competition, labor income share, the Antitrust Law  ,