The invention relates to a security monitoring device for a power distribution station. The security monitoring device for the power distribution station comprises a detecting and alarming device, controlled equipment, monitor terminal equipment and a power supply device, and specially further comprises a master control device, wherein the master control device mainly comprises a single chip, and a GSM communication module, an SIM card slot, a wireless transmission module and the like connected with the single chip, and the master control device is in wireless or wired connection with the detecting and alarming device, in wired connection with the controlled equipment, and in wireless two-way communication connection with the monitor terminal equipment. The security monitoring device can monitor whenever a power supply station is invaded illegally, record the illegal invasion fact and take corresponding measures such as driving, frightening and shutting, thereby avoiding damages to property and safety as the power supply station is invaded illegally.