In order to prevent the manhole cover to be stolen and destroyed, a detection method based on sound signal processing, which was for detecting the behavior of stealing and destroying manhole cover, was proposed. Because there were differences in the distribution of energy in frequency between different sound signals, the vibration sound signal generated by the manhole cover was transformed into the energy spectrum by using FFT method. Specific distribution interval on the frequency axis and distribution threshold of the vibration sound signal could be determined by using statistical method. It could be judged whether the vibration sound of the manhole covers was caused by the robbery and knocking by calculating the probability distribution value in the specific distribution interval of 20 maximum energy points of other interference sound signals. Experiment result indicates that the energy distribution of the percussion sound is significantly different from other interference sound. The characteristic frequency range of its energy distribution is 48~504 Hz and the distribution threshold is 85%. The method can be used to effectively identify the sound of stealing and destroying the manhole cover and has strong robustness under a certain SNR environment.