A picture hanging tool (10) is provided for facilitated marking of a selected point on a wall (14) or the like for subsequent installation of a fastener used for hanging a picture (12) or other object from the wall. The tool includes an upper handle section (16) adapted for manual grasping, and a lower support or base section (20) having a hook (30) or the like for temporarily supporting the object for movement over the wall surface to a selected precision mounting location. When the desired mounting location is obtained, an actuator mechanism (48) including an actuator pin (62) exposed on the upper handle section is operable to displace a spring-loaded marking element (38) into engagement with the wall surface at the desired point for subsequent fastener installation. The tool is then removed from the wall, the fastener installed at the marked point, and the object hung from the installed fastener.