Using satellite remote sensing data and hydrological observation data, this study investigated the cold water in the lee of the Batanes Islands in the Luzon Strait. The formation of cold water in climate is mainly due to the geostrophic heat advection on the east and west sides of the Batanes Islands: the Kuroshio separates into two branches on the east and west sides of the Batanes Islands. These two branches cause two warm tongues by transferring heat from low latitudes to mid-latitudes, and then the two warm tongues lead to the formation of the relatively cold water in the lee of the Batanes Islands. Further study shows that the cold water range has obvious seasonal and inter-annual variations. Except for August, the seasonal variation of the cold water range is caused by the interaction of geostrophic heat advection and net surface heat flux, whereas the low temperature in August in the lee of the Batanes Islands is caused by the island wake effect. The inter-annual of the cold water range is related to the dif-ference in the meridional velocity between the east and west sides of the Batanes Islands, and the correlation coefficient can reach?0.68 at the 95％ confidence level.