The present invention provides a label printer, including an upper cover module and a bottom case module configured to cooperate with the upper cover module in printing. An elastic wall is disposed at an articulating part between the upper cover module and the bottom case module. An inclined surface is provided at a corresponding position of the lower cover module. When the upper cover is opened upward to the maximum extent, a tail end of the elastic wall cooperates with the inclined surface to form a support structure to prevent the upper cover module from falling due to the gravity and the like when the upper cover module is opened.