Nowadays, studies on uptake of heavy metals in aquatic organisms have increased because of increasing of these metals due to human activities and entering of them in aquatic environment. understanding of the toxic effects of metals on fish is difficult due to that fish sometimes migrate long distance, so that doses and duration of metal exposure vary during the life cycle. The objectives of this study are Compersion of bioaccumulation factor of heavy metals (cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb) and chromium (Cr)) in the tissues two freshwater  fish species, in two different levels of food.  For this reason, these two fish species were sampled in international Anzali Wetland in summer 2009. According to the comparison bioaccumulation factor was found in least BAF in large Carassius gibelio with Omnivore levels of food in muscle tissue( Cr = 291, Cu = 554 , Pb = 190 , Cd = 141), exception of coppr metal in little Carassius gibelio mucle tissue (BAF= 1022) and with Esox lucius with level carnivore minimum BAF in muscle tissue to large size (Cr= 305, Cu=686, Zn=1070, Cd=134) exception of lead metal with BAF= 155 in muscle tissue little size. According to the results generally suggest that carnivors levels with BAF is lower than the omnivors.