Yamana Munetoyo served as a bushō during the Sengoku period.
Munetoyo was born as the eldest son of Yamana Suketoyo (Sōsen), a sengoku daimyō, head of the Tajima-Yamana clan, and the military governor of Tajima Province.
During the middle of the sixteenth century, Suketoyo fought against Yamana Nobumichi of the Inaba-Yamana clan over governance of Inaba Province. In 1546, at the Battle of Hashizugawa, Suketoyo defeated the Amago clan who support the Inaba-Yamana, causing the end of the Inaba-Yamana. Suketoyo positioned his younger brother, Yamana Toyosada, in the role of de facto military governor and turned Inaba Province into his territory.
After the demise of Toyosada in the third month of 1560, there was no one to replace him as the military governor of Inaba so Munetoyo, as the eldest son of Suketoyo, was sent to Inaba.
During the Edo period, in records of the Miyamoto family who served as merchants in Yonago, there is a letter issued by Munetoyo to Murakami Shinjirō, a member of the Murakami clan serving as the landlords of Yodoe in Hōki Province in which he stated that for purposes of fighting against the Amago forces there would be deployments from Tajima and Inaba to Hōki.