This paper investigates the features of GSCs in the process of the gonad development of sex reversal in Monopterus albus by the histological methods and the histological immunochemical techniques. In Monopterus albus, the GSCs are located in the gonadal lamellae,which are scattered or accumulated during the female phase. In the intersex and the male,the GSCs are distinguished by two types A and B, both of them differ from the GSCs at the female stage in ultrastructure. It shows that the GSCs existing in the gonadal lamellae are the unique germ family, which owns the capability of mitosis in the differential gonads. The GSCs represent the ovogonia in the female phase, while the spermagonia in the intersex and the male phases. CD49 is the molecular marker for the GSCs at the female stage and the GSCs of type A.