The coordinated development of the digital economy among members of the Regional Comprehensive Economic Partnership (RCEP) has provided new impetus for optimizing China's service trade export structure. Based on panel data from RCEP11 member countries between 2010 and 2020, this paper constructs a two-way fixed effects model to systematically examine the impact mechanism of member countries' digital economic development on China's service trade export structure. The study finds that an increase in the level of digital economic development significantly boosts the expansion of China's knowledge-intensive and digitally-driven service trade exports. This effect is realized through improved labor productivity, enhanced factor structure, and reduced trade costs. Further heterogeneity analysis reveals differences in this effect across different income countries. This research expands the theoretical framework for upgrading service trade structures from a regional digital cooperation perspective, providing policy insights for deepening the integration of digital elements and optimizing China's service export structure under RCEP.