The invention discloses an optical method-Perot partial discharge sensor installation method at a large-scale power transformer clamp member portion, belonging to the electric device field. The invention solves the problem that the optical method-Perot partial discharge sensor which is used for local discharging for inducing the supersonic wave signal can cause the electric field change inside the large scale power transformer and thus affects the operation of the large scale power transformer. The optical method-Perot partial discharge sensor is fixed inside of the angle of the large scale power transformer clamp member through the epoxy resin, which, basically, does not cause the electric field change inside the large scale power transformer, and guarantees the stable operation of the large scale power transformer. The installation method of the invention is applicable to the installation of the optical method-Perot partial discharge sensor at the clamping portion of the large scale power transformer.