The observation indicates the head length of sperm 6. 5..m, the top of broad-head 1..m, the lower part of head 1..m, neck 0. 5..m and tail length 16..m under scanning electron micro scope ( SEM) . The sperm.. s tail has axle and two wings. There are 6- 9 micropyles on the animal pole of the mature egg of Acipenser schrenckii , all of which are able to accept sperm. The micropyle.. s outer diameter is 18..m and inner 6..m. There are micropyle cells f illing in micropyle. The micropyle cells disappear after fert ilization 10s. The micropyles are sealed with membrane after sperms penetrating. The fertilization is got through about in two minutes. The sperms not penetrating egg are blocked on the way. Amur sturgeon.. s sperm and mature egg are different from those of other sturgeons.