By using the event of M&A among medium and small sized board and growth enterprise market during the period from 2011 to 2013, we make a study of the effect of performance compensation commitment on the M&A synergy in the M&A transaction and how such effect influences the distribution of gains between both parties. The result demonstrates that the introduction of performance compensation commitment remarkably raises the level of M&A synergy effect and such advancement mainly comes from the signal function of such commitment. Further, we still find that on the one hand, such commitment pushes the M&A overage, on the other hand, it also increases the shareholders profits. So we believe the wise use of VAM on M&A will Improve the efficiency of M&A.