To investigate the impacts of the total dissolved gas(TDG)supersaturated water with sediments on fish due to flood discharge from high dams, rock carp(Procypris rabaudi Tchang)and chub(Hypophthalmictuthys molitrix)were chosen as test objects and acute exposure experiments were performed to investigate the effects of TDG supersaturated water on different species. Tolerance and difference were analyzed based on the indexes of abnormal behavior, death rate, and median lethal time of the fish. The experimental results show that abnormal behaviors and symptoms of bubble disease are obvious on the test fish during the initial stage of the experiment and the abnormity was found firstly on rock carp. Under the same TDG supersaturated water condition, increase of sediment concentration can lead to a decreased median lethal time for both rock carp and chub, but the latter has longer median lethal time, revealing that chub has much stronger adaptability and endurance capacity. Moreover, when TDG supersaturation level remains a high value, even low sediment concentration can cause a high mortality of fish. TDG supersaturation level is the major reason for fish death, but the acceleration effects from sediment cannot be ignored.