The present invention provides a quick coupler sensing device capable of preventing an accident by stably recognizing a fixed state of a quick coupler and an operating device at a desired position by preventing an impact caused when a coupling unit of an operating device is coupled to a fixed part of the operating device and preventing damage and an error of driving due to a working environment of an excavator in which contaminated water remains. The quick coupler sensing device provided in the fixed part of a quick coupler (2) including a body (21) rotationally fixed to an arm (a) ad a push link (p) of an excavator and allowing a coupling part of an operating device (3) to be accommodated and fixed thereto. The fixed part has an accommodation recess (27) to which the coupling part is accommodated. The quick coupler sensing device (1) includes a main body (13) disposed in the fixed part and having a guide space (12) to allow a permanent magnet (11) to make a linear reciprocal movement in a state that the permanent magnet (11) is in contact with the inner lateral side of the accommodation recess (27) and a connector (15) provided on an inner side of the main body (13) and having a portion to which the permanent magnet (11) disposed in the guide space (12) is coupled by magnetic force.
