This study breaks through the homogeneity of mergers and acquisitions (M&A) and the dyadic relationship between the acquirer and the target firm. We consider the network content of technological diversity that reflects both acquirers–target firms and target firms–target firms. The study empirically explores the impact and mechanism of technological diversity in M&A network on the high-quality development of enterprises (HQDE). Our study reveals that technological diversity in M&A network has an inverted U-shaped effect on HQDE. Mechanism analysis shows that the technological diversity in M&A network affects HQDE through both the quantity and quality of technological innovation. The findings provide novel insights to enable acquirers to select appropriate target firms and overcome technological innovation dilemmas, thus advancing toward high-quality development.