A high-voltage equipment contact temperature on-line monitoring system based on an optical network belongs to the technical field of electrical equipment monitoring and mainly comprises a transformer station control chamber, a monitoring host, a single mode optical cable, a fiber grating signal demodulation instrument, a fiber grating signal sensing network analyzer, an optical cable terminal box and the like. The high-voltage electric equipment temperature real-time monitoring system based on the fiber grating temperature measurement technology is developed specifically to high-voltage and strong electromagnetic interference characteristics of an electric system. The advanced fiber grating temperature sensing technology is adopted. The high-voltage equipment contact temperature on-line monitoring system is advantaged by being high-voltage resistant, free of electromagnetic interference, intrinsically safe, long-term reliable, small in size, easy to expand and the like, and is suitable for carrying out real-time on-line monitoring on monitoring points of generators, high tension switchgears, ring main units and the like of generating and power supplying systems.