Narimori, who was defending the camp established near mountains with his older brothers, was killed by the army commanded by MINAMOTO no Noriyori on February 7, 1184 in the Battle of Ichinotani.
寿永3年（1184年）2月7日、一ノ谷の戦いにおいて、兄たちとともに山手の城戸口の防備にあたったが、源範頼の軍の手にかかり戦死。