Terashima Morinori served as a bushō from the Sengoku to Edo periods.  Morinori was a retainer of the Jinbō clan of Etchū Province.  He may have been the adopted son of Terashima Motosada, the lord of Ikeda Castle in the Niikawa District of Etchū.  Along with his brother, Kojima Kunitsuna, Morinori was known as a brave soldier.

In 1562, at the Battle of Kanayamura against the Uesugi, Morinori claimed one head for which he received a written commendation and increase to his stipend from his lord, Jinbō Nagamoto.  After the demise of the Jinbō family, Morinori served the Uesugi and received recognition of his rights to his territory in the Goishō area of Etchū.  In 1581, Morinori acted in concert with an invasion of Etchū by Uesugi Kagekatsu by holing up in Tomisaka Castle, but he was suppressed by the Oda army and fled to Ōdō Castle.  Thereafter, he converged with followers of the Ikkō sect from Gokayama and former retainers of the Jinbō clan to continue resistance against the Oda army.  In the wake of the Honnō Temple Incident in the sixth month of 1582, Morinori joined with Yuhara Kuninobu (the younger brother of Ishiguro Naritsuna) to pursue the Oda forces retreating from Uozu Castle.

After the pacification of Etchū by Sassa Narimasa, Morinori served on his behalf with a stipend of 5,000 hyō (sacks of rice).  Morinori also participated in the attack on Suemori Castle.  After Narimasa surrendered to Toyotomi Hideyoshi, Morinori served Maeda Toshiie, and, in the era of Maeda Toshinaga, received an income of 1,500 koku.  His descendants were members of the Kaga domain in the Edo period.