The perimeter security system of unmanned substation existing has the situation that detection means single, each security technology works independent and cannot achieve linkage. This has seriously affected on the security level of unmanned substation. In view of this problem, this paper designed a linkage solution which combined multiple security technologies. The system used laser fence to detect and locate the intruder, electronic fence as a physical means to prevent invasion, IP cameras for remote monitoring and intrusion evidence collection. It made the transmission of control and alarm information possible by using ZigBee sensor network in substation security system. The system realized detection, obstruction, obtain evidence, recording, alarm, remote video monitoring and other functions in perimeter intrusion, it also achieved linkage of various security technologies. This system solution has a certain role in promoting the security level of unmanned substation.