The influence of heavy metals (copper, 7inc) on the concentration of calcium, phosphorus and magnesium in the tissues (vertebra, gills, muscles and eye) of fish was studied. The investigation has revealed that concentrations of these elements before and after experiment are different. Due to the influence of heavy metals the level of calcium decreased by 5 and 11.5 times, in gills and muscles respectively. and increased 2 times in eyes. The concentration of magnesium decreased by 4.25 times in vertebra and by 2 times in eye, and increased in gills by 2 times. The level of phosphorus varies less than of the rest two elements.