According to the study of the formation of andalusites and sillimenites aoct it，s geologicalal significance of the Mesozoic regional metamorphic belt along the coast in Fujian Province the writer suggests that the types of the formation of those two kinds of mineral are very complax, i. e. they represent a very different geological occurrences. It is not suitable to suggest that the appearance of andalusites and sillimanites hold a special characteristic of P-T condition Which is the base of subdivision of metamorphic phase. The writer suggests that the metamorphic belt in this region was the result of the Mesozoic primary volcanic-sediments by the processes of diagenesis, regional metamorphism, migmatization, and the empeacemet of granite, and the different types of aadalusiteand sillimaates were formed by the transformation of the heat energy in each period of those processes that have been mensioned.