Abstract: The mounting frame of the present invention is constructed for being easily installed in the wall of a building from the exterior side of the wall using only a simple hand tool, such as a screwdriver, and for slidingly receiving a ventilator in a quick and simple installation procedure. The mounting frame has an outwardly extending peripheral flange on the front thereof which is adapted to engage the exterior face of the wall, and includes clamping means extending rearwardly of the peripheral front flange for engaging the interior face of the wall and clamping the frame in place in the wall. Inwardly extending flanges on the top and bottom walls of the frame are provided for engaging the rear of the ventilator to limit rearward movement of the ventilator.