Private First Class Killian was a member of Company F, 2nd Battalion, 5th Infantry Regimental Combat Team. He was Killed in Action while fighting the enemy near Chungnyong-san, North Korea on 25 April 1951. His remains were not recovered. His name is inscribed on the Courts of the Missing at the Honolulu Memorial.

Killian was awarded the Purple Heart, the Combat Infantryman Badge, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.