Asonuma Motohide served as a bushō during the Sengoku and Azuchi-Momoyama periods.  He was a retainer of the Mōri clan, serving as the lord of Tokonoyama Castle and head of the Asonuma clan.

Motohide was born as the lineal heir of Asonuma Hirohide, a kokujin, or provincial landowner, based in the Senoarayama manor in the Aki District of Aki Province.

For the Bunroku Campaign beginning in 1592, Motohide joined the army of Mōri Motoyasu and crossed to the Korean Peninsula.  On 6/15, while based in Jinghe, Mōri Terumoto dispatched Ueno Zenemon as a messenger to Mōri Motoyasu to order the pacification of Andong, strategically located in the northeast portion of Gyeongsang Province.

Motoyasu led Motohide and other bushō under his command and, on 6/22, entered Andong.

On 11/29 of Keichō 2 (1597), his father, Hirohide, died.  For the Keichō Campaign beginning in 1596, Motohide obeyed Mōri Hidemoto and made another crossing to the Korean Peninsula.  After engaging in numerous battles, he participated in the urgent construction of Ulsan Castle in Ulsan, but, just prior to its completion, on 12/22 of Keichō 2 (1597), at the First Siege of Ulsan Castle, Motohide, along with other retainers of the Mōri including Reizei Motomitsu and Tsuno Ieyori, was killed in action during a sudden attack by 1,000 light infantry soldiers serving under the command of 擺寨 in the vanguard of the Chinese army.  As a result, Motohide’s lineal heir, Asonoma Motosato, inherited the headship of the clan.