Feeding behavior is one of the important behaviors of fish. Through quantitative analysis of feeding behaviors of different kinds of fish based on feeding sound signals, one can judge the density of the fish cluster and improve the utilization efficiency of fish feed in aquaculture. In this study, cameras and hydrophones were used synchronously to monitor the feeding behavior of largemouth bass, and acoustic synchronization method was used to explore the relationship between feeding behaviors and sound signals of largemouth bass at different breeding densities. It was found that the frequency range of different largemouth bass feeding signals and background noise in the environment was 1-10 kHz. The pulse width of largemouth bass feeding signals was mainly concentrated within 3ms, and the difference of largemouth bass with different body length was the least in the first formogram. The phonation frequency of largemouth bass was not correlated with its density. The phonation frequency range of largemouth bass was 1-10 kHz at different densities. The SPL of feeding sound signals of largemouth bass varied under different densities, and there was a positive linear correlation between SPL and density.