Abstract: To analyze the activities of digestive enzymes in the unfertilized and fertilized eggs of Carassius auratus, we detected the enzyme activity in the various development stages using biochemistry methods. Results showed that compared to the unfertilized eggs, the fertilized eggs had significantly high level of activities for the 5 digestive enzymes, and the order of the activity level was amylase>trypsin>lipase> pepsin>cellulase. At the various embryo development stages, the enzyme activity for the 5 digestive enzymes changed in different manner. The activity of amylase decreased in a wave-like manner when the embryo was developing, while the activities of trypsin, lipase,pepsin and cellulase increased.