The utility model discloses a roller shutter releasing mechanism, which comprises a mounting frame, an electromagnet, a swing plate, a roller shutter rolling mechanism and a guide plate. The roller shutter rolling mechanism comprises a roller shutter fixing shaft, a roller shutter and a roller shutter rolling shaft, the roller shutter fixing shaft is fixed into the mounting frame, one end of the roller shutter is fixed to the roller shutter fixing shaft, and the rest of the roller shutter is wound on the roller shutter rolling shaft. The guide plate is obliquely mounted in the mounting frame, the roller shutter rolling shaft is arranged on the guide plate, the bottom of a slope of the guide plate is positioned at the lower edge of an opening of the lateral face of the mounting frame and provided with a movable hinge hinged to the lower end of the swing plate, and the electromagnet is fixed onto a top plate of the mounting frame and attracts the upper end of the swing plate. The roller shutter releasing mechanism has the advantages of simple structure, convenience in use and high reliability.