The membrane morphological change during embryonic development of Northern Sheatfish (Silirus soldatovi) in Heilongjiang river was observed by scanning electron microscopy and optical dissecting microscopy. The egg surface structure of the demersal and adhesive eggs before and after artificial debonding was also observed. The results showed that the surface of fertilized egg envelope was composed of a layer of thin and dense material with porous structures. The jelly coat on viscous fertilized egg envelope surface was smooth and dense, with many holes connected by trabecular connection (desmosome). With embryonic development jelly coat gradually expanded, unfolded, thinned and, finally naturally shed at the rupture envelope period. Artificial debonding almost took off all jelly coat and the egg lost its adhesivity. The egg envelope surface without jelly coat was coarse and composed of irregular particles and the chain structure around the particles. The structure showed little change during the embryonic development until the embryo hatching out of the envelope. However, the particles gradually lost and ruptured in late embryonic development. The fertilized egg vivisection was also conducted and the relationship between the structure and change of egg envelope and its function was discussed.