In order to investigate function of cell division cycle 20 homolog （Cdc20），in the present study，the coding sequence （CDS） of Megalobrama amblycephala cdc20 gene was cloned，and the domains and evolutionary relationship of Cdc20 were analyzed based on multiple sequence alignment and phylogenetic analysis.The temporal and spatial expression patterns of cdc20 were detected by semi-quantitative reverse transcription PCR （sqRT-PCR），quantitative real-time PCR （qRT-PCR） and in situ hybridization.The results showed that the cdc20 CDS of M. amblycephala is 1 482 bp in length and encodes 493 aa.Multiple sequence alignments and phylogenetic analysis revealed that amino acids sequences of Cdc20 were very conserved through evolution and consisted of seven-bladed β propeller structure，which was formed by seven WD40 motifs.The similarity of M. amblycephala Cdc20 was the highest with those of Danio rerio and Cyprinus carpio.Based on qRT-PCR，the mRNA levels of cdc20 were the highest at the zygote stage，and gradually decreased with the development of embryos.Additionally，the cdc20 gene also exhibited tissue-specific expression pattern，which was abundant in the gonads based on sqRT-PCR.The results of in situ hybridization showed that the cdc20 mRNA was widely expressed in all stages of M. amblycephala oocytes，mainly in the cytoplasm of stage Ⅱ oocytes and the yolk granules of stage Ⅲ and Ⅳ oocytes. In the testis，the cdc20 expression was the highest in spermatogonia and reproductive epithelium，but low in sperm.In conclusion，the results suggested that the M. amblycephala cdc20 may be a maternal gene and play a vital role in the development of germ cells.