In order to utilize shellfish larvae resources in the ocean and optimize the technique for larvae collection of Mizuhopecten yessoensis and Mytilus edulis, collection bags were set in coastal areas of the Yellow Sea in Lvshun for larvae collection. nine groups of collectors were set 2m, 3m, 4m, 5m, 6m, 7m, 8m, 9m and 10m from water for 40d to observe the quantity of larvae of Mizuhopecten yessoensis and Mytilus edulis and research the effect of different depth of seawater on the larvae collection. The results showed that, in the depth of our trail, the number of M. yessoensis larvae collected was increasing as it went deeper, and in a depth of 6m or more, a good number of larvae were collected, but it didn’t show a significant difference in quantity; the number of M. edulis larvae collected decreased as the depth got greater, and a depth of 5m or less brought a good quantity without significant difference in quantity, while it got decreasing sharply when it went to 5m or deeper. Thus, for larvae collection of M. edulis, a depth of 5m or less would be better, and 2-3 meters would be optimal; for M. yessoensis, a depth of 6m or more was recommended.