The invention discloses a detection and deployment system for a sensor on electrical equipment and a deployment method. The method comprises the following steps of establishing a three-dimensional physical model of the electrical equipment, and determining a partial discharge area on the three-dimensional physical model; dividing a part corresponding to the partial discharge area on the three-dimensional physical model into a plurality of grid models with the preset size; selecting a fixed number of candidate position points on the surface of the three-dimensional physical model for many timesin order to obtain a plurality of sensor deployment modes of corresponding times; traversing each sensor deployment mode, and computing a corresponding discharge signal at the center point of each network model and arrival time of the discharge signal transmitted to the corresponding candidate position point; and screening out the sensor deployment mode of the actual deployment sensor on the electrical equipment shell from the sensor deployment modes according to the computed arrival time. The system and the method solve the technical problem of difficulty in deploying the sensor on the electric equipment due to the fact that the internal structure of the electrical equipment is complex when partial discharge detection is carried out in the prior art.