The invention discloses a detection device and method for mechanical parameters of an electric isolation disconnecting link. By adopting an incremental rotation photoelectric encoder, a sensor is installed on a main shaft of an electric isolation disconnecting link mechanism to serve as a sensor for measuring the rotating speed, and a main shaft angular displacement time curve in the operation process of an electric isolation switch is obtained; data of voltage, current and active power is acquired through a Hall sensor based on a Hall effect; the two sensors are in data communication with a controller through an interface chip MAX 485. The detection method for the mechanical parameters of the electric isolation disconnecting link well solves the problem of isolation switch mechanical parameter detection of the isolation switch in a transformer substation live environment; by means of the parameter testing, the defects of the isolation switch can be accurately grasped, and the development trend of hidden dangers can be predicted.