The invention provides a quick coupling for a machine power supply. The quick coupling is characterized by comprising a fixed end and a movable end, wherein the fixed end comprises the components, such as a power box conducting terminal; the movable end comprises the components, such as an insulating housing; the power box conducting terminal is connected with a power line; a fixed end socket is used for insertion of a movable end plug; the power box conducting terminal is fixed on a terminal block conducting plate through a conducting bolt A; the fixed end socket is fixed on the terminal block conducting plate through a conducting bolt B; a machine power cable connection terminal is fixedly connected with machine power cables; the movable end plug is fixed on the insulating housing; an insulating bolt passes through the insulating housing; the machine power cable connection terminal is fixed on the insulating housing; and the machine power cables are electrically connected with the movable end plug. The quick coupling is small in volume and convenient to use, the operation time is shortened, the labor intensity and the labor cost are reduced and the operation risk is reduced.