The invention provides an automatic automobile trim coating device with a sewing thread. The coating device comprises a lower mold and an upper mold. The upper mold is provided with a lifting mechanism, and side pushing mechanisms for clamping workpieces on the lower mold are arranged on both sides of the lower mold. The lower mold comprises a lower mold body, lateral lower molds, a lower mold mounting plate, sewing thread middle jacking molds, a main spring component and an auxiliary spring component. Two symmetrical sewing thread middle jacking mold mounting grooves are formed in edge positions, close to both sides, of the lower mold body. The sewing thread middle jacking molds are mounted in the sewing thread middle jacking mold mounting grooves. The automatic automobile trim coating device has the advantages that the sewing thread middle jacking molds with positioning and suction functions and the side pushing mechanisms are added to the lower mold, automatic coating of trim products can be realized; front and back edges of a cover are sucked by vacuum suckers to guarantee the shape stability of the sewing thread during coating, the position degree and flatness of the sewing thread after coating are also ensured, and accordingly, the products meet quality standards.