In this paper, multiplication techniques and development of the clam, Cycli na sinensis applied in saltern were studied, as well as related to the clam's morphology and construction, growth, season, size and constitution. The multiplicational experiments, which lasted for more than two years, were conducted in the No. 1 Reservoir with an area of 382. 6 hm2 for resource conservation and the rest of 84. 1 hm2 for seeding transplantation. As a result, the total yield of the clam increased 959. 3 tons and up to 9. 1 times in the resource conservation area; and in the seeding transplantation area the clam increased 270. 7 tons and up to 8. 7 times. A total multiplieational profit of 7. 32 million yuan(RMB) was obtained.