Abstract: The monazite samples of various genetic types are taken fro m different localities in China and have been analysed by EPMA. The available analytical data show that the monazites of magmatic granite and pegmatite have l ower contents of La (4％～13％), Ce (18％～28％) and higher contents of Sm (2％ ～5％), Gd (1％～3％), Y (1％～3％), Th (3％～7％). The monazite of hydrothermal metasomatic origin has higher contents of La (12％～18％), Ce (>28％), and lowe r contents of Gd (<0.3％), Th (0.1％～0.3％) and Y (0.06％～0.14％). The composi tional change profiles of monazite demonstrate a heterogeneous distribution of e lements La, Ce, Nd, P, Th, Si, Ca and U. This was caused by the differences in geological environments, temperatures, pressures and compositions of the hy drothermal solutions.