Nagaoka International Corp. engages in the operation of water treatment facilities. It operates through the Energy-related and Water-related segments. The Energy-related segment manufactures and sells petroleum refining and internal equipment called Screen Internal for petrochemical plants. The Water-related segment manufactures and sells screen for water intakes. The company was founded by Masuzo Nagaoka on October 10, 1934 and is headquartered in Osaka, Japan.