Abstract: Pengze crucian carp, just like silver crucia n carp, is known as gynoge netic crucian carp. It is one of the most popular cultural fishes in China. The offspring of pengze crucian carp activated by heterogeneous sperms show obvious allogynogenetic biological effects in growth, rate of fertilization and other as pects. But like in silver crucian carp, no evidences have been found that the al logynogenetic biological effects exist in morphology or protein phenotype in pen gze crucian carp. That is why there are argument about the phenomenon of allogyn ogenetic biological effects. In this paper, the patterns of expressions in four isozymes (EST, MDH, ME and LDH) were investigated in the embryogenetic stages of gynogenetic crucian carp (Carassius auratus of Pengze) activated by homogen ous and heterogeneous sperms, respectively, used by polyacrylamide gel electroph oresis. The material used here were collected from Nanhai Aquiculture Experiment Base, College of Life Science, South China Normal University. Both MDH and LDH showed apparent differences between the embryos activated by homogenous sperm an d those by heterogeneous sperm. The main differences in MDH exist at hatching st age, which showed two more bands in the isozyme pattern of embryos activated by heterogeneous sperm than those of embryos activated by homogenous sperm. The mai n differences in LDH exist at five stages from middle-gastrula to muscle constr uction, which showed four more bands in the isozyme pattern of embryos activated by heterogeneous sperm than those of embryos activated by homogenous sperm. Mea nwhile, the other two isozymes (EST and ME) detected in this paper did not show apparent differences between the embryos activated by homogenous sperm and those activated by heterogeneous sperm. Furthermore, the speed of development of the embryos activated by heterogeneous sperm is slight faster than that of the embry os activated by homogenous sperm. Although it is difficult to define the reason of the above differences, it can be considered as one form of allogynogenetic bi ological effects.