Artificial induction of maturation by heating of the ark shell, Scapharca broughtonii (Schrenck) broodstock was investigated from 10th March to 21th May in 2004. Maturity at the fixed water temperature group of 23℃ was 60.5％, and it was the highest in maturity among experimental groups cultured for seven weeks. The proportions of organism surviving to start of S. broughtonii in the raised water temperature experimental groups (20 and 23℃) were over 90.5％, as similar to the control group (natural water temperature, 84.8％). But, the proportions of organism surviving to start of S. broughtonii in the fixed water temperature experimental groups (20, 23, and 26℃) were decreased with the increasing of the water temperature. In the fixed water temperature experimental groups of 26℃, the survival was 18.1％. Base on these results, the fixed water temperature of 20℃ (accumulated water temperature; 1,295℃) was the best condition for artificial induction of sexual maturation.