Polymerase chain reaction PCR was induced in seashells, use of 20 primers yielded 391 amplified fragments; 2 individuals of Haliotis discus hannai Ino, yidded 65 amplified fragments between 501 to 2818bp; 3 individuals of Seapharca suberenata Lischke , yielded 76 amplified fragments between 398 to 2818bp: 3 individuals of Mactra veneritormis Deshayes, yielded 154 amplified fragments between 562 to 331lbp; and 2 individuals of Mactra chinensis Philippi,yielded produced 96 amplified fragments between 478 to 331lbp. The result indicated that seashells have abundant genetic poligmorphism. RAPD can be used to facilitate study on the taxonomy and the phylogeny of seashells.