The invention provides a safety guarantee system for an urban municipal comprehensive pipe gallery. The system comprises a PCB, a GSM communication module, a GSM antenna, an MCU, an emitter, a receiver, a camera, a door bolt, an outer side contact, an inner side contact, a middle spring and an inner side spring, wherein the emitter emits microwaves which are complexly reflected in the pipe gallery and finally arrive at the receiver; the MCU judges that the environment in the pipe gallery is abnormal according to the changes of received microwaves to start the camera to collect image information; and the image information is transferred to a management department through the GSM communication module and the GSM antenna, and work staff takes action according to the image information. Metal wafers which are connected to a system trunk line in series are adhered to the inner end of the outer side contact and the outer end of the inner side contact; and after the pipe gallery door is closed, the bolt pushes the outer side contact to move toward the bolt hole, so that the two metal wafers are in contact, and the system is electrified to be started. The system has important meaning for promoting municipal foundation facility construction, guaranteeing overall coordinated development of urban space and creating a good urban ecological environment.