A method for bonding a three-dimensional cover, which includes the following steps: bonding a flexible display panel on a heavy release film through optical adhesive to obtain a bonded body; placing the bonded body on a carrying surface of a conformable tool, making the flexible display panel face the carrying surface of the conformable tool, and fixing two ends of the heavy release film in the bonded body to fixtures of the conformable tool; controlling the fixtures of the conformable tool to adjust the shape of the bonded body, so that the adjusted shape of the bonded body matches the three-dimensional cover; tearing off the heavy release film from the bonded body to obtain the flexible display panel with optical adhesive, and bonding the three-dimensional cover to the flexible display panel using the optical adhesive.