The Yashan topaz-lepidolite granite contains high phosphorus (P2O5 = 0. 15%~0. 55%) and high fluorine (F = 1. 07%~2. 04%), and is one of the representative F- a nd P-rich granites in South China. It is strongly peraluminous (A /NKC=1. 26~1. 60), very high in Li, Rb, Cs, Be, Nb and Ta and very low in Y and REE. Atnblygonite is the most important phosphorus mineral of the Yashan topaz-lepidolite granite. Whether the amblygonite occurs or not is closely related to the Li, Rb and Cs contents of the melt. Both amblygonite and feldspars are the main hosts of whole-rock phosphorus in the Yashan topaz-lepidolite granite. If amblygonite is present in the granite, the mineral is the main contributor of whole-rock phosphorus and feldspars are the subordinate contributor; if no amblygonite crystallizes out, feldspars will be the main contributor of whole-rock phosphorus. Apatite, monazite and xenotime are very difficult to attain saturation under conditions of the strong peraluminous natureand very low REE, Y and Ca contents. Apatite in granite is present in small amount and mostly crystallizes in the late magmatic stage. Monazite and xenotime are rare in the topaz-lepidolite granite , which implies that there occurred differentiation of the REE phosphatic minerals such as monazite and xenotime during the magmatic evolution of the Yashan batholith. The occurrence of hydroxylherderite suggests that Be- and Ca-bearing hydrothermal fluids operated in the Yashan granite in the postmagmatic stage.