The weakening of the East Asian summer monsoon intensity during the Younger Dryas (YD) event has been well documented in paleoclimate archives, yet the spatiotemporal patterns of hydroclimatic variability across monsoonal eastern China remain debated. Here, we present multi-proxy records based on precisely dated speleothems from Xianyun (XY) Cave, Southeastern China, featuring by average 5-year-resolved 518O/513C and 21year-resolved (Mg/Sr)/Ca ratios during 13.66-10.69 kyr B.P. The stalagmite 518O amplitude across the YDPreboreal transition in Xianyun Cave is 0.26 parts per thousand, which is probably the smallest recorded among all studied caves in the eastern Monsoon Region of China (MRC). While the XY stalagmite 518O profile confirms monsoon weakening during the YD, the first principal component analysis of 513C and Mg/Ca reveals sustained relatively wet conditions in Southeastern China throughout this interval. A comparison of 18 paleoclimate proxies across the East Asia MRC expressed a meridional tripole ("-+-") hydroclimate mode along the North China - South China - South China Sea coastal transect during the YD. We propose that a southward migration of the summer monsoon rain belt, modulated by the southward shift and intensification of the westerlies and the southwestward extension of Western Pacific Subtropical High, resulted in the spatial heterogeneity of hydroclimate in the MRC during the YD.