The top management team (TMT) is a key resource for an enterprise’s sustainability, and the study of TMT characteristics is very important to explain the factors involved in an enterprise’s development. In order to comprehensively evaluate the impact of TMT characteristics on enterprise performance in China, the effect of average characteristics and vertical dyad characteristics of TMTs on enterprises performance was researched in this paper. This study is based on upper echelon theory, the similarity–attraction paradigm, and social categorization theory, stemming from the dual perspectives of social psychology and social politics. The concept of chairperson–TMT vertical dyad similarity is first proposed as a TMT characteristic, and the effect of vertical dyad similarity on enterprise performance is empirically analyzed using panel data from 235 manufacturing small- and medium-sized enterprise (SME) samples. The findings demonstrated that TMT average tenure, TMT age vertical dyad similarity, and tenure vertical dyad similarity have a significant positive effect on enterprise performance, while TMTs’ other average characteristics and chairperson–TMT vertical dyad differences have no significant effect on enterprise performance.