A method for contactless measurement of the conductivity of thin conducting film was demonstrated. In order to apply the technique to on-line testing, a large standoff distance of 35 mm was obtained by using a reflector focusing sensor. The measurement was preformed by using a microwave compact equipment working at 94 GHz which was developed for decreasing the system cost. Indium Tin Oxide films having conductivity of 8.2 × 104 ~ 6.6 × 105 S/m on the glass substrates were used as the samples. Evaluation equation for determining the conductivity of Indium Tin Oxide films was generated.