The invention relates to a fiber grating implanted 110kV composite coat zinc oxide lightning arrester and its preparation method. In the lightning arrester, a plurality of fiber Bragg grating sensors are uniformly connected to a 700mm optical fiber in series, and the length of a tail fiber is at least keep at 1500mm. The optical fiber with a plurality of fiber Bragg grating sensors is implanted into the epoxy sleeve of the 110kV composite coat zinc oxide lightning arrester, and each fiber Bragg grating sensor is respectively wound together with a valve plate group tightly by epoxy tailless belts. The tail fiber is extended out of a low-voltage end fitting hole of the 110kV composite coat zinc oxide lightning arrester. The most visualized advantages of the lightning arrester lie in that, it can substantially save manpower and financial resources, and can accurately monitor the lightning arrester valve plates' real-time heating performance that is hard or impossible to measure by manualmeasurement methods, indirectly reflect the change of its electrical properties, and solve various problems brought by manual measurement methods, thus filling the domestic gap in the field.