Lifespan: Unknown to Genki 2 (1573)
Title: Governor of Sagami (informal)
Lord: Itō Yoshisuke → Itō Suketake
Father: Itō Sukemasu
Siblings: Sukemune, Sukemoto
Itō Sukemune served as a bushō during the Sengoku period. He was a retainer of the Itō clan of Hyūga Province.
Sukemune was born as the son of Itō Sukemasu, a retainer of the Hyūga-Itō. He was the son of a cousin of Itō Yoshisuke. As a member of the Itō family, he served in an important role for Yoshisuke.
In the ninth month of 1551, when the Itō clan attacked Mei Castle to the southeast of Obi in the Minami District, he killed Niiro Kawachi-no-kami of the Shimazu-Hōshū (a cadet family of the main branch of the Shimazu family) who had been assigned as the lord of the manor. Sukemune also participated in a battle at Itajiki in 1558 and in a battle at Mimida in 1567.
In particular, in the twelfth month of 1558 (or, alternatively in the sixth month of 1559), Sukemune led a small force in battle at Itajiki to the north of Obi Castle to repel forces led by Shimazu Naohisa sent by Shimazu Muneie to reinforce the castle. He killed thirteen prominent bushō from the Shimazu including Harunari Hyōgo-no-kami and Nara Nagato-no-kami. Members of the Itō clan extolled his victory as an extraordinary achievement in any era.
In 1568, during the Ninth Campaign of Obi, Sukemune commanded an army of 3,800 soldiers to lay siege to Obi Castle. To pin-down the castle, he set-up a base at Niiyama and contributed to the capture of the castle. After the Hōshū-Shimazu clan vacated the castle, Sukemune served as the guardian for its new lord, Itō Suketake and was granted landholdings totaling thirty hectares and provided support to Suketake with quarters in the Ima citadel on the grounds of Obi Castle.