Abstract: The aim of this paper was to explore the bio- accumulation and release characteristic of Cd in different organs of Mytilus Edulis. In this paper,the Cd concentrations in organs were assayed by using the method of atomic absorption spectroscopy.The results indicated that the content of Cd in visceral mass,anterior and posterior adductor muscle,mantle and gill of M.edulis were 145.56,11.826,28.143,2.394 and 66.113 mg / kg respectively,after15 day 's accumulation. The value of uptake rate constant( k) of different organs was high during the early accumulation,then was decreased during intermediate period,and increased again during the later period.While,the bio- accumulation factor( BCF) was decreased with the increasing concentration of Cd in water during the whole accumulation.The order of k and BCF values were visceral mass,gill,posterior adductor muscle,mantle and anterior adductor muscle,when M.edulis were under the same exposed time.Correlation and multivariate analysis showed a significant time- dependent relationship between the accumulated content of Cd( Y) and the exposed time( X),with R2= 0.9286 ~ 0.9890 values of Harris model( Y = 1 /( a + b Xc). However,the content of Cd in four organs of M.edulis was not declined significantly during the whole releasement.The obtained results indicated that M.edulis as the net accumulated biological could not release a large amount of heavy metals.