The present invention relates to a coupling device, in particular to a waterproof coupling device, comprising an inserter, a coupler, a sealing cover, a data bridge module, a live wire bridge module and a neutral bridge module, and the inserter is provided with a live wire insert The input terminal, the neutral line insertion terminal, the data insertion terminal and the insulating layer covering the outer surface of the live wire insertion terminal, the neutral line insertion terminal and the data insertion terminal; the coupler is divided into a coupling chamber and a sealed cavity The external matching thread outside the chamber and the sealing chamber, the coupling chamber and the sealing chamber are separated by a barrier layer provided in the coupler, and the barrier layer is provided with a live wire coupling sleeve, a neutral wire coupling sleeve, a data Coupling sleeve, data through hole, live line through hole, neutral line through hole and sliding sleeve cooperate with the extension sleeve; the invention can be used immediately after insertion, one step in place, with anti-shock design; has multiple waterproof effects, can be used in water, and adopts Modular design for easy repair and replacement parts.