In this study, the amount of nickel and vanadium elements in the soft tissues of rock oysters (Saccostrea
cuculata) and sea water from coastal areas of Qeshm Island, the biggest island of Persian Gulf located in the south of Iran, were measured to evaluate the contamination of the aquatic environment and organisms. Following the bioassay, weighing and chemical digestion of the samples, finally the amount of nickel and vanadium in the soft tissues of the oysters and sea water samples were measured via the ICP system. The results indicated that the average concentration of nickel and vanadium found in the sea water were respectively: 15.7 and 37.9 micro grams per liter and in the soft tissues of oyster: 2.44 and 1.91 mg per kg respectively. In comparison with the FDA and WHO standards, only the concentration of nickel in the soft tissues of oysters was in a permitted level, and the rest exceeded the permitted levels. The average concentration of metals in the north side of the island were more than that found in south of the island but
this difference was not statistically significant (p> 0.05).