China's climate actions through energy transition have exacerbated regional disparities in the energy-economy-environment (3E) system. This study introduces regional equity metrics (Gini coefficient and Theil index) into the 3E framework, establishing a multi-objective optimization model to coordinate carbon reduction and regional development during 2021–2030. Four strategies were developed with key findings: All scenarios reduce regional inequality, with economic output Gini coefficient declining by 8.73–9.52 %, energy intensity Gini by 28.35–44.2 %, and carbon intensity Gini by 8.77–14.54 %, while achieving carbon peaking. China requires 5.1 % annual GDP growth with provincial target adjustments. Spatial analysis identifies critical provinces for energy transition (Beijing, Shanghai, Liaoning, Hebei, Shanxi, Inner Mongolia) and carbon mitigation (Jiangsu, Shandong, Guangdong, Hebei, Shanxi, Henan), revealing their disproportional impacts on national targets. The comprehensive strategy proves most cost-effective, reducing emissions at 144.91 yuan/ton while generating 104.59 trillion yuan GDP (2005 prices). Its provincial quota allocation mechanism optimally balances equity and efficiency. This study provides a replicable framework for reconciling climate targets with regional equity, offering critical insights for China's coordinated transition.