Murakami Yoshimitsu served as a bushō from the Sengoku to Edo periods.  He was the sixth head of the Innoshima-Murakami clan.  He had the same name as the third head of the clan.

Yoshimitsu was born as the son of Murakami Naoyoshi, a bushō from Bingo Province.

The Innoshima-Kurakami clan, along with the Noshima-Kurakami and the Kurushima-Murakami were bands of seafaring pirates controlling the Seto Inland Sea.  From the era of Yoshimitsu’s father, Naoyoshi, the Innoshima-Murakami were closely aligned with the Mōri clan based in Aki Province.  In 1555, at the Battle of Itsukushima, the Innoshima-Murakami were called upon by the Mōri and Kobayakawa clans to join their forces, whereupon the Innoshima-Murakami navy was dispatched under the command of a senior retainer named Suenaga Kagemichi (later known as Isokane Kagemichi).  Serving as one wing of the Kobayakawa navy, the Innoshima-Murakami made significant contributions toward the victory achieved by the Mōri.

Thereafter, Yoshimitsu associated with the Mōri and Kobayakawa clans and, from 1555 to 1557, during the Subjugation of Bōchō (Suō and Nagato provinces), among other operations, he participated in a blockade of the Kanmon Straits.  On 1/12 of Kōji 3 (1557), Kobayakawa Takakage conferred upon him the title of Keeper of Imperial Archives of the Sixth Rank.  After the Mōri began to battle against the Ōtomo clan, in 1561, at the Siege of Moji Castle, Yoshimitsu served under the command of Nomi Munekatsu to repel the Ōtomo army.

In 1576, at the First Battle of Kizugawaguchi, Yoshimitsu fought valiantly and decimated the Oda navy, contributing to the ability of the Mōri to supply provisions to the Ishiyama-Hongan Temple.  In 1582, when Kurushima Michifusa of the Kurushima-Murakami clan surrendered to the Oda clan, Yoshimitsu remained with the Mōri.  Subsequently, Mōri Terumoto granted Yoshimitsu landholdings of 400 koku in the Tsuno District of Suō Province and 500 kan from one-half of the annual rice levies on shrines and temples in Suō and Nagato.

Yoshimitsu did not have a natural son.  His younger brother, Murakami Sukeyasu, had a son named Kagetaka so Yoshimitsu adopted him but Kagetaka died early so he received Kagetaka’s younger brother, Yoshisuke, as his designated heir.

After the Battle of Sekigahara, accompanying the reduction in the fief of the Mōri clan, Yoshimitsu moved to Nagato Province and was granted a fief of only 1,800 koku (or 2,800 koku) so he split from Murakami Motomitsu (Yoshisuke’s son and the head of the family) and returned to Innoshima where he died.