The invention discloses an inlaying plastic compressing sealing method for a contact element. The inlaying plastic compressing sealing method for the contact element comprises the following steps: 1) preparing an injection mold: keeping the injection mold clean and undamaged; 2) preheating: heating the injection mold to 160+10/-5 DEG C; 3) opening the injection mold and putting the contact element into the injection mold. The molding is adopted and the identifying number can be added to the surface of a multi-core contact part; the electric property, mechanical property and environment property of the epoxy molding compound are excellent; the temperature shock resistance and hydraulic pressure cycle performance are excellent; the consistency of product quality is excellent; the appearance is smooth and beautiful; the strength is high; the contact element is difficult to be damaged; the electric connector product has longitudinal water sealing property; under non-plugging state or interface failure of the water sealing connector, with a longitudinal water sealing structure, the connector also has independent sealing property.