He was the victor at the Battle of Uji in 1180, and also at the Battle of Yahagigawa in 1181, where, after forcing the enemy Minamoto forces to retreat, Tomomori fell ill, and so the pursuit was ended. Tomomori was again victorious over the Minamoto in a naval battle at Mizushima two years later. The Taira forces tied their ships together, to create a larger stable surface to fire arrows from, and to engage in hand-to-hand combat. At the Battle of Dan-no-ura, when the Taira were decisively beaten by their rivals, Tomomori joined many of his fellow clan members in committing suicide. He tied an anchor to his feet and leapt into the sea.
Tomomori has become a popular subject for kabuki plays.