The purposes of this paper are to exam the relationships among corporate governances, diversification strategy in mergers and acquisitions and performances for family firms. We use Taiwan Listed companies as subjects and the research period is from 1996 to 2005. Final empirical evidences show that controlling stockholders play an important role in M&A performances, and making diversification strategy decisions. Moreover, diversification strategy in mergers and acquisitions has negative influences on short-run M&A performances.