Optical fiber perimeter intrusion alarm system

The invention discloses an optical fiber perimeter intrusion alarm system. The system comprises an alarm host, an optical fiber distribution frame and sensing communication multiplex defense areas which are connected in sequence; the alarm host is connected with the optical fiber distribution frame, and the optical fiber distribution frame is connected with the sensing communication multiplex defense areas through communication optical fiber cables; each sensing communication multiplex defense area comprises an optical module, a terminal module and sensing fibers, wherein each optical module is in communication connection with the optical fiber distribution frame through one or more communication optical fibers in the communication optical fiber cables. According to the optical fiber perimeter intrusion alarm system, sensitive optical cables between optical modules and terminal modules in the optical fiber perimeter intrusion alarm system defense areas are replaced with unoccupied communication optical cable cores among the defense areas, under the circumstance that the same effect as the traditional optical fiber perimeter intrusion alarm system is guaranteed, the material cost of the sensitive optical cables is removed, and the purposes of reducing the cost and simplifying the structure can be achieved.