The embodiment of the invention provides a crushing machine safe protection method and device. The device comprises a signal detection module, a crushing machine control module and a crushing machine driving motor, wherein the signal detection module is provided with a crushing machine observation door and is coupled with the crushing machine control module; the crushing machine control module is coupled with the crushing machine driving motor; the signal detection module is used for detecting the open or closed state of the crushing machine observation door, and sends a state signal used for expressing the open or closed state of the crushing machine observation door to the crushing machine control module; the crushing machine control module is used for receiving the state signal and sends a starting or closing instruction to the crushing machine driving motor according to the state signal; the crushing machine driving motor is used for receiving the starting or closing instruction sent by the crushing machine control module, starting the crushing machine driving motor according to the starting instruction, and closing the crushing machine driving motor according to the closing instruction. The device has the advantage that high safety can be realized when work personnel enter equipment to repair.