The present invention discloses a waterproof plugging device for a power cable pipeline. The device comprises a pipeline 1, a power cable, a pipeline 2, a plugging housing, a sealing element 1, a sidesealing structure, a pin shaft, an upper cover, an upper plugging structure, a sealing pad, a sealing ring, a lock, a fixed base, a water pumping pipe, a sealing element 2, a water collection cavity,a waterproof separator, a right water pumping channel, screws and a left water pumping channel. The waterproof plugging device for a power cable pipeline is simple and reasonable in structure and lowin production cost, and the waterproof separator is arranged to effectively isolate water between the pipeline 1 and the pipeline 2 so as to avoid a phenomenon of water in a pipeline influencing thewhole pipeline; the right water pumping channel and the left water pumping channel are arranged to facilitate pumping of water generated from the pipeline; the side plugging structure and the upper plugging structure are arranged to effectively perform compression and sealing of the power cable, and the upper side between the connection of pipelines is subjected to tripling compression and sealingto effectively prevent water from flowing through the side surface of the power cable so as to improve a sealing effect.