Iwama Dōjō, Shinto shrine in Kasama, Japan

Aiki Jinja is a single-story wooden shrine on a low stone base, with a broad dark grey gabled roof and a lighter band beneath the eaves. Four square pillars carry a projecting porch across a facade of three bays, the central entrance recessed behind dark double doors, and a narrow veranda runs along the base. Its Honden was completed in 1943 and the larger Haiden set in front of it in 1962.

Morihei Ueshiba bought the land in 1940 and moved to Iwama in 1942. The first part of the Aiki Shrine, the Honden, was completed in late autumn 1943, and the larger Haiden was added in front of it in 1962. The shrine was renovated in 2001–2002 under Morihiro Saito, and a bronze statue of Ueshiba was unveiled on 8 November 2009.

The shrine's name is written on a stone stele carved by Seiseki Abe, a calligrapher who was also Morihei Ueshiba's own teacher of brushwork. Each 29 April the Aikikai holds its annual festival here with a demonstration of aikido offered to the kami, drawing about 1,500 practitioners, many from abroad. While Ueshiba lived, he led a monthly ceremony, Tsukinamisai, lasting up to an hour, with fruit, vegetables and fish placed on the kamidana.

The shrine and its grounds stand in the Yoshioka district of Kasama, in the former town of Iwama. The Ibaraki Branch Dojo holds general classes every day for regular students, while live-in students train three times daily and also maintain the dojo and shrine precincts. The dojo was rendered unusable by the 11 March 2011 earthquake, and practice moved into the Haiden until the repaired hall reopened on 17 September 2011.

The shrine's name stone was carved by Seiseki Abe, an aikido master who was also Morihei Ueshiba's calligraphy teacher. A large bronze statue of the founder was unveiled in the grounds on 8 November 2009, and leftover metal from it was cast into a bust displayed at the rebuilt Iwama Station in 2012.