Abstract: The Chinese sturgeon (Acipenser sinensis) is an endangered national protected species and also an important resource for sturgeon culture industry. However, only a few genes have been identified in this species. We report here the two subtypes of its proopiomelanocortin, POMC from a pituitary cDNA library of a 24 years old female Chinese sturgeon just after its spawning. Among all the 2025 EST clones, the AsPOMC-A and AsPOMC-B appeared 128 and 19 times, respectively. The nucleotide sequences of AsPOMC-A and AsPOMC-B are 1122 and 1216 bp in length, respectively, and encode for mature peptides both of 264 aa. The Chinese sturgeon POMC contains the segment corresponding to -melanocyte stimulating hormone (-MSH) (Y76-S97), adrenocorticotropic hormone (ACTH) (S140-I178), -lipotropic hormone (-LPH) (D181-E209), -melanocyte stimulating hormone, (-MSH) (AsPOMC-A: D212-D228; AsPOMC-B: G212-D228) and -endorphin (Y231-Q264), respectively. The phylogenetic tree of POMCs among Chinese sturgeon and other fishes was constructed by neighbour-joining method and maximum parsimony which indicated a divergence of the fish in Neopterygii and other fishes. The Chinese sturgeon POMCs showed greater sequence identity on average with ancient ray-finned fishes including acipenseriformes (89%-99%) and semionotiformes (70%) than with agnathan (31%-33%), elasmobranchii (40%-45%), chimaeriformes (33%-36%), and dipnoi POMCs (57%-63%). Interestingly, Chinese sturgeon POMCs showed obvious variety in sequence identity in teleostean (35%-70%). Furthermore, we analyzed their phylogenetic significance and suggested that AsPOMC-B might be an ancestral gene, and might play significant roles in reproduction regulation of ancestral fishes.