Abstract: A lens measuring instrument has a transparent base plate which includes upper and lower lens supporting surfaces. A generally L-shaped measuring member supported for movement on the base and across the upper surface thereof has a measuring surface movable toward and away from an opposing first reference surface which projects above the upper surface of the base and against which a peripheral edge portion of a lens supported on the base may be abutted. A second reference surface projects below the lower surface and provides an abutment for a peripheral edge portion of a lens supported by the lower surface. The first and second reference surfaces lie in a common plane normal to the upper and lower surfaces of the base. A dial indicator operably connected to the measuring member and indicia of linear measurement carried by the measuring member provide means for indicating the position of the measuring surface relative to the first and second reference surfaces.