Kumaichi Teramoto joined the Imperial Japanese Army in 1910, being commissioned into the infantry.

When war broke out with the United States in December 1941, he held various air staff assignments.

However, he was invited into the Army Aeronautical Department in the Ministry of War, and in 1944 he became the head of its Credit Bureau.

The next year he became Acting Inspector-General of Army Aviation and in late 1945 he became the head of the entire organization.

On August 15, when Japan surrendered to the United States after the nuclear bombing of Hiroshima and Nagasaki, Kumaichi Teramoto committed seppuku, the ritual suicide of Japan.