Born in Columbus, Ohio, he was educated in Columbus and at Ohio State University in civil engineering before joining the new Air Corps in 1928 through the ROTC. He was commissioned as a second lieutenant in 1930. He transferred to bomber aircraft in 1937 and soon demonstrated excellent abilities. At the outbreak of World War II he was a group commander in the 8th Air Force. By early 1942 he was a lieutenant colonel and directed the 305th Group into action over Europe. He was given command of the 3rd Bombardment Division in late 1942 and in July 1944 he transferred to Pacific operations. He was promoted to major general and directed the 21st Bomber Command, heading B-29 operations including the massive incendiary attacks on over sixty Japanese cities, such as Tokyo on March 9-10, 1945 during which around 100,000 people were killed. So he was called "brutal LeMay" (鬼畜ルメイ) by Japanese.
Post-war he was briefly transferred to The Pentagon as Deputy Chief of Air Staff for Research & Development. In 1947 he returned to Europe as commander of USAF Europe, heading operations for the Berlin Airlift in 1948. He was back in the US by 1949 to replace George Kenney in command of the Strategic Air Command. He headed SAC until 1957, overseeing its transformation into a modern, efficient, all-jet-engined force. He was appointed Vice Chief of Staff of the United States Air Force in July 1957, serving until 1961 when he was made Chief of Staff on the retirement of Thomas White.
He was not a success as Chief of Staff; he was a belligerent and totally committed anti-Communist and clashed repeatedly with more flexible minds, such as Robert McNamara, Eugene Zuckert, and General Maxwell Taylor. LeMay lost a number of significant appropriation battles (for Skybolt ALBM, the F-111, and the B-52 replacement, the XB-70.) He also lost in his desire for a much more vigorous engagement in Vietnam. The quote "we should bomb Vietnam back into the stone age" is often, if erroneously, attributed to him. However, his passion for strategic over tactical strikes did come to be reflected in the Air Force, which became disproportionally strong in favour of strategic bombing operations during his tenure. He retired in February 1965 and a potential political career reached no further than vice presidential candidate to George Wallace in 1968.