The invention discloses an IM type AC insulation monitor signal processing system comprising a reception amplification circuit, and adjusting circuit and a clamping voltage stabilizing circuit; the reception amplification circuit receives and amplifies a signal, the adjusting circuit adjusts the signal, and the clamping voltage stabilizing circuit clamps, stabilizes and outputs the signal. The reception amplification circuit receives the IM type AC insulation monitor voltage signal, and the adjusting circuit uses a dual-triode to adjust the signal, thus improving the signal antidamping property; the clamping voltage stabilizing circuit clamps and stabilizes the signal, thus improving the signal anti-interference capability; the IM type AC insulation monitor signal processing system uses fewer elements, is easy to repair, and no single-chip microcomputer or microcontroller are employed.