Also known as: Oota Sukenaga (太田資長)

Oota Doukan was a Japanese samurai warrior-poet, military tactician and Buddhist monk who is best remembered for designing and building Edo Castle (now the Imperial Palace). He served the Ougigayatsu-Uesugi Clan and built Edo Castle for Uesugi Sadamasa over Edo Shigenaga's earlier fortifications. In the 16th century, Tokugawa Ieyasu would choose Edo Castle to be his home upon his transfer to the Kantou.

During Nagao Kageharu's Rebellion, Doukan fought 30-odd battles and almost single-handedly averted the crisis for the Ougigayatsu and Yamanouchi Uesugi clans. His efforts resulted in a great increase in the influence of the Ougigayatsu-Uesugi Clan as well as his own stature.

The Ougigayatsu-Uesugi Clan, fearful and suspicious of his rising power (possibly justified, possibly not) had Doukan assassinated at Uesugi Sadamasa's residence in Sagami.