Knowledge transfer in technological acquisitionM&A can improve the innovation performance of enterprises, but as the acquirer, Chinese enterprises are not as advanced in technology as the object of the merger, which leads to the inability of Mmerger and acquirer&A enterprises to effectively manage the process of knowledge transfer. In order to clarify the internal mechanism of knowledge transfer promoting technological innovation in mergers and acquisitions, and explain the influence mechanism of knowledge congruity, strategic complementarity, organizational fitness and other factors on knowledge transfer efficiency, This paper adopts the method of case study is adopted and tookakes Haier Group''s merger and acquisition of Fisher & Paykel GroupFPA as the research object to study the mechanism of Chinese enterprises'' technological innovation through cross-border merger and acquisition. The results show that the factors such as knowledge congruity, strategic complementarity, organizational fitness in the process of transnational technology mergers and acquisitionsM&A are conducive to the knowledge transfer between acquirer and objectiveM&A firms, and ultimately improve the innovation performance of acquirerM&A firms. kKnowledge congruity, strategic complementarity, organizational fitness enhanceenhances the influence of knowledge transfer on enterprise innovation performance. From the perspective of knowledge transfer research, knowledge consistency can improve absorptive capacity and reduce the cost of knowledge transfer. From the perspective of merger and acquisitionM&A research, strategic complementarity and organizational matching provide a guarantee mechanism for knowledge transfer. Finally, this paperit is proposesd that in the process of acquiring key technologies through cross-border merger and acquisitionM&A strategy, Chinese enterprises should evaluate the knowledge consistency, strategic complementarity and organizational matching with acquisitionthe M&A targetobjective, which can improve the absorption capacity of acquisition objectivethe M&A enterprise, enhance the cross-organizational innovation network and connection between the merger and acquirerM&A parties, and make knowledge transfer easier between the merger and acquirerM&A parties. Eventually innovation performance between the merger and acquirer is improved the m&a enterprise innovation performance.