Abstract:As one of the oldest subcold water fish, Acipenser barei is valuable in term of fish research and economy. In order to provide information that may help with the improvement of artificial propagation and evolutional development study, the morphological observation during embryonic development of A.barei were studied under rearing conditions. Under 15.5-18.0 ℃, it took 133 h from fertilization to hatching with the average cumulation temperature of 2 173-2 369 ℃·h. The embryonic development process could be divided into 7 stage, including fertilized egg stage, cell division stage, blastula stage, gastrula stage, neurula stage, organ formation stage and hatching stage, and contained thirtyfour developing phases, each of which the characteristics were described. The cleavage pattern is radial holoblastic cleavage, and is similar to that of amphibian, but not obviously different with many other fishes; however, the disc cleavage is something like that of bony fish.