Fish biological sounds reflect abundant information of its living state. It is important to systematically conduct research on the fish acoustic features. This paper designs program code based on Fast Fourier Transform (FFT) to deal with the sounds in frequency domain. By applying the program to analyze the sounds of piranha, oyster toadfish etc., the feature of main frequency is obtained and the sound features of different fishes are compared. This paper further designs the sound detection experiment about the acoustic spread distance; analyzes the sound decibel value varying trend according to the result. The different features among the fishes illustrate the sound difference. Acoustic spread detection experiment provides the fish behavior control feasible distance in the taming system design.