Shared auditors as a network of social relationships can facilitate the transmission and sharing of information between enterprises within the network. Using a sample of domestic mergers that acquirers and targets are all A share listed firms from 2004 to 2016, this paper analyzes whether shared auditors between the acquirer firm and the target firm can affect M&A performance, in addition, we also make a study on whether the information asymmetry can moderate the relationship. Our findings are that: shared auditors between acquirer and target has a significant positive effect on M&A performance of acquirer firms and target firms; Furthermore, the positive impact of shared auditors on M&A performance is more pronounced for cross-industry and cross-regional M&A events where information asymmetry is greater.