The implementation of RCEP and continuous construction of the New International Land-Sea Trade Corridor have boos-ted China-ASEAN trade,yet gaps in logistics infrastructure and industrial capacity across countries restrict regional logistics coordina-tion.To quantify the evolution of logistics synergy from 2012 to 2022 and identify core driving factors,this paper constructed a multi-dimensional logistics index system.The entropy weight-composite coupling coordination model was used to measure logistics synergy of individual countries,three sub-regions and the whole region,and a log-log panel fixed-effect model was applied to test marginal effects of influencing factors.The results showed that the overall coupling coordination degree rose from 0.178 to 0.829,shifting from severe imbalance to good coordination.The China-Thailand-Myanmar group reached good coordination at 0.847 in 2018,while the China-Brunei-Laos-Vietnam-Cambodia group hit 0.849 near the high-quality coordination threshold in 2022.Per capita GDP,logistics employment,transport network and digital penetration promoted synergy significantly,while government fiscal expenditure with coefficient-0.114 presented restraining effect due to unreasonable fund allocation.Targeted suggestions covering differentiated infra-structure construction,unified cross-border logistics standards,optimized fiscal investment and regional intelligent logistics platforms were proposed to advance integrated regional logistics development.