During World War I Huebner served on the Western Front and was sent to France with his regiment, the 28th Infantry, which later became part of the 1st Infantry Division ("The Big Red One"), shortly after the American entry into World War I. The division was the first of the American Expeditionary Force (AEF) to be sent overseas during the war. The following year he participated in the first American regimental assault at Cantigny, through Soissons, Saint-Mihiel, and the Meuse-Argonne. For his service in this war, he received two Distinguished Service Crosses, an Army Distinguished Service Medal, and a Silver Star. He commanded the 2nd Battalion, 28th Infantry at Cantigny after his commanding officer was killed, and later commanded the regiment, one of the youngest regimental commanders in the AEF.