Abstract: A dolly for lifting one end of a long open web steel joist or truss and for then conveying the joist to and fro along a steel structural beam member having a horizontally disposed web which normally restingly supports the joist. The dolly includes a main body which carries an axle having a wheel journaled thereto for runningly and ridingly engaging the beam member as the joist is manually maneuvered into its optimum position. A lever or handle is fixedly attached to the main body and coacts with the wheel (which acts as a fulcrum) to lift the heavy joist as the handle is manually urged downwardly. Various embodiments of structure for engaging and supporting two different type joists are disclosed herewith.