The invention provides a rotor collecting device. The device comprises a first conveying belt, a driving mechanism, a pressure sensor and a controller, wherein a supporting seat is arranged at the feed end of the first conveying belt; the supporting seat comprises a first supporting plate, a second supporting plate and a third supporting plate; the first supporting plate and the second supporting plate are respectively vertically arranged at two sides of the first conveying belt; the third supporting plate is arranged between the first supporting plate and the second supporting plate and is rotatably connected with the first supporting plate and the second supporting plate; the pressure sensor is arranged on the third supporting plate; the driving mechanism is connected with the third supporting plate to drive the third supporting plate to overturn; and the pressure sensor and the driving mechanism are electrically connected with the controller. The device provided by the invention has the beneficial effects that through the cooperation of the supporting seat, the driving mechanism, the pressure sensor, the controller and the conveying belt, when the weight of rotors on the third supporting plate is up to a preset value, the driving mechanism is controlled by the controller to drive the third supporting plate to downward overturn by 90 DEG and the automatic stacking, collecting and conveying of the rotors are realized.