JA Building, Office skyscraper in Ōtemachi, Japan

The JA Building is a 180 m office tower completed in April 2009 in Ōtemachi, Chiyoda, Tokyo. Its broad facades are clad in pale warm-grey stone or concrete panels set in a dense grid of identical rectangular windows, with a narrow recessed band of lighter panels running down the face and a strip of dark vertical fins along the left edge. It forms a linked trio with the neighbouring Nikkei Building (155 m) and Keidanren Kaikan (122 m), joined at low level by the 140 m glass curtain wall of the Ōtemachi Conference Center.

The current tower opened in April 2009 alongside the neighbouring Nikkei Building (155 m) and Keidanren Kaikan (122 m), its 180 m height set between them to avoid a uniform wall of towers. It replaced the 1965 JA Building designed by Takeo Satō, which stood about 400 m to the east-southeast and was demolished; the Ōtemachi Financial City South Tower rose on that site in 2012. The three new buildings are linked at their lower levels by the 140 m glass-curtain-wall Ōtemachi Conference Center.

The building houses organizations focused on agricultural development, serving as a meeting point between urban Tokyo and rural farming communities. Inside, cooperative societies work on initiatives that connect city and countryside.

The tower stands at Ōtemachi in Chiyoda, beside the Nikkei head office and the Keidanren Kaikan; the three are joined at their lower levels by the 140 m glass curtain wall of the Ōtemachi Conference Center. Ōtemachi Station serves several subway lines, and the Marunouchi and Tokyo stations are within walking distance. The upper floors are rented offices, so visitors stay in the shared lower levels.

The three towers on the block were deliberately given different heights to avoid a cramped wall of identical buildings: Nihon Keizai Shimbun at 155 m, the JA Building at 180 m and Keidanren Kaikan at 122 m. Their lower floors are joined into the Ōtemachi Conference Center, whose 140 m glass curtain wall encloses rooms that can host international conferences.