Chousokabe Motochika was a daimyo of Tosa Province and 20th head of the Chousokabe Clan. He was the eldest son and heir of Chousokabe Kunichika, the 19th head. He was decorated for his first campaign at the age of 22.

After he succeeded as clan head, he took control of the entire Tosa Province, then managed to take Awa Province, Sanuki Province, and Iyo Province at the fall of the Miyoshi, Sogou, and Kouno clans, respectively. However, his hold over the four provinces lasted for just a few weeks, for he lost the three provinces he had gained in the Siege of the Four Provinces in 1585 to Toyotomi Hideyoshi (then still serving Oda Nobunaga).

During the next decade, Motochika fought several campaigns under Hideyoshi with his sons, including the Siege of Odawara in 1590 in which he led the Chousokabe Navy.

He died of illness in 1599 and was succeeded by his fourth son Chousokabe Morichika.