OAP Tower, Office skyscraper in Tenmabashi, Japan

The OAP Tower is an office building in Tenmabashi that rises 39 stories and stands 176 meters tall. Most of its interior space houses office areas where many different companies operate daily.

The site was the Osaka smeltery of Mitsubishi Metal, closed in 1989; Mitsubishi Materials and Mitsubishi Estate then redeveloped it as Osaka Amenity Park. OAP Tower was completed in January 1996, followed by the art court in 1998 and the residence towers in 1998 and 2000. Some buildings echo the smeltery's forms, and parts of the old structures were moved and rebuilt on site.

The complex's buildings echo the Osaka smelter that once stood here, with details modelled on the refinery and some structures moved and rebuilt on site. The OAP port beside the Okawa river is the departure point for the Aqua Liner sightseeing boat and the Himawari cruise boat.

The complex sits in Tenmabashi, Kita Ward, on the former Mitsubishi Metal Osaka smelter site beside the Okawa River. Sakuranomiya Station on the Osaka Loop Line is a five-minute walk; Osaka Tenmangu Station on the JR Tozai Line, seven; Minamimorimoto on the Tanimachi and Sakaisuji subway lines, ten. Free shuttle buses run to Umeda, Honmachi, Minamimorimoto and Yodoyabashi, and the Osaka Suijobus Aqua Liner and Himawari boats call at the OAP port inside the complex.

The complex occupies the former site of Mitsubishi Metal's Osaka smelter, which closed in 1989. Parts of the development imitate the smelter's architecture, and some structures were moved here and rebuilt. The OAP port also serves the Aqua Liner and Himawari river boats on the Okawa.