Under the background of the deep integration of the digital economy and the real economy, digital transformation has become a crucial pathway for China's dairy enterprises to achieve high-quality development. This paper employed a mixed-method approach combining empirical research and case study analysis to systematically investigate the impact of digital transformation on the financial performance of China's dairy enterprises. Using panel data from 24 A-share and H-share listed dairy companies in China from 2016 to 2024, a two-way fixed effects model is constructed for empirical testing. The results revealed a significant U-shaped nonlinear relationship between digital transformation and long-term corporate financial performance. In the initial stage of transformation, the high costs of digital construction exert a negative impact on financial performance; however, as digital transformation deepens, its positive effects gradually emerge, significantly enhancing financial performance. Heterogeneity analysis indicates that the impact of digital transformation on financial performance is more pronounced in state-owned enterprises. Furthermore, this study conducted a horizontal comparative analysis of four leading dairy enterprises—Yili Group, Mengniu Dairy, Bright Dairy, and Tianrun Dairy—using DuPont financial analysis, Palip financial analysis, and operating cash flow analysis to assess their financial performance in 2023 and 2024. The findings showed that factors such as improper post-merger integration, asset impairment provisions, high tax burdens, and low conversion efficiency of operating cash flow contribute to significant fluctuations in financial performance. Based on these findings, this paper proposed policy recommendations including strengthening post-merger integration management, promoting product diversification and brand building, and improving ESG governance. This study provided theoretical insights and practical guidance for optimizing digital transformation pathways and enhancing financial performance in China's dairy industry.