The purpose of this paper is to assess the R&D investment of Korea Gas Corporation (Kogas) by combining several measures including R&D needs, technology spillover effects, and technology stock at the corporate level. This study has revealed that Kogas has concentrated its R&D resources on the operation and maintenance of gas supply facilities, and technology groups, which have higher fulfillment of R&D needs and technology spillover effects, have been on the relatively greater level of technology stocks.