This study involves a relationship between butyltins concentrations and histopathological changes of the digestive gland in the equilateral venus, Gomphina veneriformis exposed to TBTCl of 0.4, 0.6 and 0.8 μg/L for 36 weeks. In the sediment, total butyltin (？BT) concentration was detected ND~7.54 (0.4 μg/L), ND~9.76 (0.6 μg/L), 1.22~13.13 μg/L (0.8 μg/L), respectively. Especially, TBT level in 0.8 μg/L group was the highest for 36 weeks. In the soft tissue, total butyltin (？BT) concentration of the exposure group was 10.14~12.75 (control), 479.29~1,286.56 (0.4 μg/L), 563.32~2,154.82 (0.6 μg/L) and 1,317.70~2,132.60 μg/L (0.8 μg/L), respectively. Ratio of TBT to ？BT of the tissue of 0.8 μg/L kept the lowest level for 36 weeks. The ？BT concentrations of sediment were correlated with ？BT concentrations in the tissue. In the exposure groups, necrosis and atrophy of columnar epithelial cell and collapse of epithelial layer in the digestive tubule. And there was a reduction in stain affinity of basophilic cell. Such histological degenerations was more severe in digestive tubule of 0.8 μg/L group. Key words : TBTCl, Gomphina veneriformis, accumulation, digestive gland