A wall-mounted Christmas tree device serving as a festive holiday decoration that takes up minimal space. This pine tree-shaped invention may be temporarily removably mounted to at least one wall and/or door or other suitable vertical surface thereby making it easy for occupants of virtually any size residence to display a beautiful, realistic festive decoration. The wall-mounted Christmas tree device disclosed herein preferably comprises the following components: at least two flat tree half outlines; a spine having a plurality of sockets; a base having electrical powering means; and a plurality of insertable branches. The Styrofoam or fiberglass flat tree half outlines may include double-sided tape or a plurality of suction cups to removably attach the wall-mounted Christmas tree device on a vertical surface. A kit for the present invention and method of use is also described herein.