This paper empirically studies the impact of institutional investors on performance of listed companies from China's Growth Enterprises Market (GEM). The empirical results show that the shareholding of institutional investors has a significant positive effect on the performance of the company, among which the shareholding of fund companies has the most significant effect. On the other hand, previous literature has pointed out that institutional investors have less effect on improving the performance of state-owned enterprises than private enterprises, however, the empirical results show that this difference is not significant in China's GEM.