This study uses a sample of technological mergers and acquisitions (M&As) of A-share listed companies in the five major high-tech industries from 2012 to 2016, and conducts factor analysis to measure the heterogeneity of these enterprises in terms of financial slack resources, equity resources, and governance structure. On this basis, multivariate regression analysis is utilized to explore the influence of the acquiring firms' heterogeneity on their innovation performance, and the adjustment action of absorptive capacity between heterogeneity and innovation performance. The research results show that the slack financial resources and highly centralized equity structure of enterprises are not conducive to enterprises improving their innovation performance following a technological M&A, while the impact of governance structure on innovation performance following an M&A is similarly not significant. The empirical evidence provided offer insights and a decision reference for technological M&As of high-tech enterprises.