Acoustic barrier is an important means to prevent fish from entering dangerous areas and protect fish resources. In order to screen fish-sensitive negative sounds as acoustic barriers, six single-frequency sounds (500-3 000 Hz) and one broadband sound (alligator roar) were used as experimental sounds to screen negative sounds of grass carp juveniles. The behavioral responses of grass carp juveniles to different sounds were compared by alternately broadcasting at both ends of the sink. The results showed that most experimental fish responded to sound, and the roar of alligator was significantly different from other sound groups. In the single-frequency sound experimental group, the average number of responses was the largest when playing 500 Hz single-frequency sound, which was 1.7 ± 0.6 times, while the average number of responses was as high as 5 ± 0.9 times when playing alligator roar, which was significantly higher than other experimental sounds. In the total average speed, the total average speed of grass carp in the broadband sound group was significantly higher than that in other groups, indicating that grass carp was sensitive to the roar of alligator and escaped. This research shows that the grass carp has a negative tendency to the roar of the alligator, and the roar of the alligator may be a sound that has a driving and deterrent effect on the grass carp. This research can provide a reference for the auxiliary means of luring and driving fish in fish passage facilities and the avoidance of fish entrainment in water conservancy structures.