Abstract: The Agulhas Retroflection (AR) region serves as a critical conduit for water mass and heat exchange between the Indian and Atlantic Oceans, and its heat transport process has a significant impact on the heat redistributions in both oceans. Based on high-resolution simulations from the OGCM for the Earth Simulator (OFES), this study quantifies the characteristics of zonal heat transport (Q_H) across the 20.0°E section within the AR region (35°S−41.2°S) during 1980−2017. We evaluated the contributions of individual components to Q_H and investigated the impacts of flow field variability. Results show that the climatological annual-mean total Q_H is westward and reaches −0.74 PW, with contributions of the Mean-flow-dominated nonlinear heat transport (Q_MEAN) and the Eddy-driven nonlinear heat transport (Q_NLR) are −0.45 PW and −0.29 PW, respectively. The heat transport induced by flow field variations (Q_VEL) exhibits the highest correlation with Q_H (r = 0.59), accounting for 43.24% of its variance. Further composite analysis reveals that the Q_VEL variability is mainly modulated by the meridional shifts, retraction/extension, and intensity changes of Agulhas Current (AC) and Agulhas Return Current (ARC). Reduced westward Q_VEL occurs when AC weakens more substantially than ARC, yielding positive Q_VEL anomalies. Conversely, enhanced westward Q_VEL coincides with strengthened AC and ARC, where southward expansion and widening of AC amplify net westward transport, generating negative anomalies. Zonal migration of the retroflection point (representing the AC-ARC system position) shows a positive correlation with Q_H variability on decadal scales. This study systematically establishes the linkage between spatiotemporal variability of the AC-ARC system and cross-basin heat transport, demonstrating that both positional and structural changes in the circulation exert critical controls on heat transfer. These findings advance understanding of AR dynamics and their broader climatic implications.