A partial discharge signal processing device of the present invention is provided with: a partial discharge signal receiving unit disposed inside a high voltage electric machine device; a partial discharge signal processing unit; and a coaxial cable connecting the partial discharge signal receiving unit and the partial discharge signal processing unit. In addition, the partial discharge signal receiving unit comprises an electromagnetic wave receiving unit that receives electromagnetic waves generated by partial discharge. Further, the partial discharge signal processing unit comprises: a detection unit that detects a partial discharge signal transmitted through the coaxial cable; a band limiting unit that limits the frequency bandwidth of the partial discharge signal; an attenuation amount correction unit that corrects an attenuated partial discharge signal; and a signal output unit that outputs, to an external device, the corrected partial discharge signal.