When do research on the location of partial discharge in power generator’s stator using ultrasonic sensor, there are many problems exist including that ultrasonic signals detection is not obvious or even ultrasonic sensor can not detect ultrasonic signals. This article researches the location distribution in power generator which is favorable for ultrasonic sensor to receive ultrasonic signals. Put forward a placement method of sensor which is applies to the partial discharge location of power generator basing on sonic pressure distribution of ultrasonic signal in the stator’s outer, which is obtained by simulating sound field of power generator stator using ANSYS Multiphysics. The placement method of sensor has laid the foundation for the future research of the partial discharge location of power generator. Through comparing the simulation results and actual experimental test, the authors find that simulation of sonic pressure is similar to experimental results, proving the placement method is validity.