Abstract: An apparatus for installing door frames which comprises at least two template members and at least three apertures on each template member. To provide horizontal adjustment means between said at least two template members, at least one elongated member may be joined approximately normal to each of said at least two templates. Said at least one elongated member may comprise at least one tongue member and at least one groove member, said at least one tongue member may be slidably positioned within said at least one groove member. To provide means for plumbing said template members, at least one screw may be positioned within said at least one template member. To install a door frame, the apparatus is positioned within a doorway, said doorway composed of two trimmer studs joined by a header stud, such that the at least one template of the apparatus is juxtaposed one of the two trimmer studs, and said at least one aperture outlines the perimeter of at least one slot to be cut in the trimmer stud.