According to relative content of terrigenous clastic rock's components (clay minerals of claystone and clastic composition of sandstone), analyzing paleoclimate of Late Cretaceous - Paleocene Nanxiong Basin in northern Guangdong and southern Jiangxi. The climate index of sandstone clastic components (feldspar/quartz, F/Q) is between 0.02 to 0.14; Clay mineral assemblage is mainly illite, with an average of 79%; Illite crystallinity index and chemical index is 0.25~0.39 and 0.31~0.7. During this period, the climate of the study area is mainly arid climate, with some warm and humid climate intermittent, paleoclimate can be divided into three stages: arid-semiarid Maastrichtian, warm and moist semiarid early Danian, and the semiarid late Danian. Climate evolution is consistent with the same period of global climate change.