Chōsokabe Moritsune served as a bushō during the Azuchi-Momoyama and early Edo periods. Moritsune was the eldest son and lineal heir of Chōsokabe Morichika, a daimyō and the twenty-second head of the Chōsokabe clan.
During the Siege of Ōsaka, his father, Morichika (who supported the Toyotomi clan) demanded that Moritsune serve in the campaign, whereupon Moritsune entered Ōsaka Castle and fought on behalf of the Toyotomi against the Tokugawa forces. After the fall of Ōsaka Castle, Moritsune and Morichika were apprehended. Morichika was paraded as a criminal around the main avenues of Kyōto and, on 5/15, was taken to an execution site known as Rokujō-gawara along the Kamo River and beheaded. Moritsune was beheaded in Fushimi in the environs of the capital. This ended the hereditary lineage of the Chōsokabe clan.