Either resistivity or thickness of conductive thin films may be measured if the other one of the properties is known. The system employs eddy current apparatus including an alternating frequency driving coil, a detector coil mounted in a housing adjacent one surface of the thin film, and circuitry for measuring the signal across the detector coil which senses the field after it is subjected to the eddy currents generated within the conductive film. Precise adjustment of a fixed distance between coils and film surface is important and achievable by positioning the film surface at the focal point of a optical microscope objective lens to which the eddy current apparatus is coupled.