Abstract: A resin molding method includes a first molding step, a sliding step, a second molding step and a mold opening step. In the first molding step, first molded part supported in a fixed mold and a second molded part supported in a die slide mold are molded in different positions in a second direction. In the sliding step, the movable mold is removed in a first direction and the first molded part and the second molded part are aligned by the die slide mold is moved in the second direction. In the second molding step, the movable mold is clamped again with the fixed mold and resin is injected into engaged portions. Each of the first molded part and the second molded part includes at least one wall extending in the first direction, and in the second molding step, the first molded part and the second molded part are engaged with each other at sides of the walls extending in the first direction.