The present invention relates to an optical cable clearance to earth intelligent monitoring and early warning device and method. According to the prior art, man-made instable factors exist in manual inspection on optical cable clearances to earth, and existing equipment is only capable of performing fixed-point detection and incapable of detecting the clearance to earth of a whole optical cable, and while, with the device and method of the invention adopted, the above conditions can be avoided. The device comprises an optical cable, a hanging wire and a sliding mechanism; and control equipment comprises a distance detection unit, a position analysis unit, a control unit, a communication unit and a solar power supply unit. With the optical cable clearance to earth intelligent monitoring and early warning device and method of the invention adopted, the clearances to earth of all positions of the optical cable can be detected, a user can know the condition of the overall clearances to earth of the optical cable more clearly and intuitively, the problem of inaccuracy of a traditional mode according to which clearance to earth detection is performed on only one point can be solved; and the categories of the clearances to earth of the optical cable can be judged according to judgment on whether the location of the optical cable belongs to a residential area, and therefore, analysis is more detailed, early warning is more accurate, and false early warning can be avoided.