Against the backdrop of the “dual carbon” goals, this study focuses on the Xizang. By developing an integrated evaluation index system for the digital economy, ecological environment, and clean energy systems, we conduct an empirical analysis using panel data (2013–2023), employing the TOPSIS entropy weight method and a coupling coordination degree model. The results indicate: (1) The overall development level of the three systems demonstrates an upward trajectory, characterized by leapfrog development in the digital economy, continuous optimization of clean energy, and an inverted U-shaped curve in the ecological environment. (2) The coupling coordination degree of the three systems has undergone a three-stage evolutionary process, with synergistic effects progressively intensifying.