Abstract: Analyzing the spatial differences and influencing factors of synergistic effects in pollution reduction and carbon mitigation within the ecological construction domain is a prerequisite for guiding regional collaborative governance. It is also a crucial component in achieving the "dual carbon" goals and advancing the construction of a beautiful China. This study employed a comprehensive analysis using the CRITIC weight method，an adjusted coupling coordination model，standard deviational ellipse，Theil index，and a two-way fixed effects model to examine the temporal and spatial evolution characteristics，regional disparities，and the influencing factors from 2010 to 2022. The results indicated that: (1) The overall level of synergy in pollution reduction and carbon mitigation showed an upward trend，with the coordination level gradually shifting from mildly uncoordinated to well-coordinated. (2) The synergy level in pollution reduction and carbon mitigation exhibited significant spatial heterogeneity，with an overall "northeast-southwest" spatial distribution pattern. The distribution center showed a trend of reciprocating migration from southwest to northeast. (3) The overall regional difference in the synergy level first decreased，then increased，and subsequently decreased again. The inter-regional differences were smaller than intra-regional differences，with the overall inter-regional differences manifesting as "midstream > downstream > upstream". (4) The degree of impact on the synergy level was in the order of energy consumption intensity，economic development，technological innovation，industrial structure，and government environmental protection efforts. Among these factors，energy consumption intensity and economic development exerted a negative constraining effect on the improvement of the synergy level，while technological innovation，industrial structure，and government environmental protection efforts had a positive promoting effect.