Okubo Tadatsune (1724-1803) was a Hatamoto in the middle of the Edo period. He was the eldest son of Tadayuki Okubo. He was the grandson of Tadayuki Okubo, known as the “Imperial Governor of Japan. His common name was Hikozaemon. In November 1744 (Enkyo 1), he succeeded to the post, and in December of the same year, he was presented to Tokugawa Yoshimune as the Goshoinban. He resigned his post in 1756 and was appointed to the post in 1789. Despite being a Hatamoto, Tadatsune was an accomplished painter and is known for his Nanpohin-style paintings.