Abstract: 152 small and medium-sized listed companies are taken as research samples, and by using multiple regression analysis, the relationship between heterogeneity of the top management team (TMT) and the enterprise performance is empirically analyzed On this basis, the moderating effect of the ownership structure on this relationship is also analyzed The results show that both heterogeneity of education level and  heterogeneity of the tenure have a significant impact on the enterprise performance The ownership structure has a clear moderating effect on relationship between the heterogeneity of TMT and the enterprise performance The proportion of the circulation shares and the proportion of the executive stock have an enhanced moderating effect on the heterogeneity of the tenure and the enterprise performance This study expands and improves the relationship model between the heterogeneity of TMT and the enterprise performance, and introduces the proportion of the circulation shares and the proportion of the executive stock as the adjustment variables, which enriches the research model based on the ownership structure as the regulating variable Some suggestions are put forward for the improvement of the right structure and the construction of TMT

Key words: top management team, heterogeneity, enterprise performance, ownership structure