The top management team is the maker and implementers of enterprise development strategy, and its stability plays a vital role in preventing major risks and maintaining stable and sustainable development of enterprises. This paper takes China’s A-share listed companies from 2010 to 2019 as samples to investigate the influence of the stability of top management team on M&A (mergers and acquisitions) behavior. The results show that the stability of top management team has a significant negative impact on M&A behavior, and the impact is more obvious in non-state-owned enterprises and enterprises with large salary gap within the top management team. In addition, the improvement of the stability of top management team can reduce the level of risk taking, reduce the inefficient investment behavior, and thus reduce the possibility of M&A. Furthermore, a stable top management team is also conducive to improving the M&A integration ability and M&A performance of enterprises, showing a higher M&A efficiency. This study is of great significance for listed companies to pay attention to the stability of top management team, reduce the blind and destructive M&A, improve the efficiency of M&A, and promote the high-quality development of enterprises.