相馬氏
was the 2nd "daimyō" of Sōma-Nakamura Domain and the 18th hereditary chieftain of the Sōma clan. He was the eldest son of Sōma Toshitane, and his mother was an adopted daughter of Shogun Tokugawa Hidetada. His courtesy title was "Nagato-no-kami" but was changed to "Daizen-no-suke" in 1636. His wife was a daughter of Naito Tadashige of Toba Domain. He became "daimyō" at the age of 7 in 1625 on the death of his father, and due to his youth, his uncle Sōma Yoshitane served as regent. In 1641, during a great fire in Edo, he was ordered by the shogunate to oversee firefighting efforts, but was seriously injured when a horse panicked. He died of illness in 1651 without a male heir.