The experiment was to study the effect of density on the growth of Amur river sturgeon (Acipenser schrencki) in two grow-out trials. Fish with average weight around 22 g were reared at the density of 0.223, 0.454, 0.663 and 0.896 kg/m3 water in the first trial for 16 weeks. Fish with average weight between 880 and 871 g were reared at 3.523, 6.988, 10.458 and 13.938 kg/m3 water for 12 weeks. In both trials, the average final weight, growth rate, feed conversion rate and condition factor of fish that were reared at high density were significantly different from those at low density. The effect of density of which the biomass was over 8-10 kg/m3 water, the growth of sturgeon was inversely related to the density, which the higher condition factor was found in fish that was reared at lower density. Results suggested that periodic sieving to reduce stocking density was necessary to enhance the growth of sturgeon.