The present invention provides a switch control circuit which comprises a branching unit for dividing the sinusoidal voltage signals generated by two ends of a piezoelectric material into the same first sinusoidal voltage signal and second sinusoidal voltage signal, a differentiator unit for converting the first sinusoidal voltage signal into a first cosine voltage signal, an analog phase shifter unit for carrying out 1/m shifting of the second sinusoidal voltage signal such that the shifted signal goes through the differentiator unit to be a second cosine voltage signal, an open loop amplification circuit unit for carrying out open loop amplification on the first cosine voltage signal and the second cosine voltage signal to obtain a first square wave signal and a second square wave signal, and a first single chip microcomputer control unit for detecting the jumping edges of the first square wave signal and the second square wave signal and alternatively outputting control signals for controlling switch on and off when the jumping edges are detected. According to the switch control circuit, the electric energy recovery efficiency of an energy recovery circuit is improved.