Maj Gen Michael Carey is being removed from command of the 20th Air Force, which is responsible for three wings of intercontinental ballistic missiles, a total of 450 missiles at three bases across the country.
The Air Force is citing "loss of trust and confidence" in Carey's leadership, but the exact reason for the firing was not immediately clear.
The decision was disclosed to the AP by officials speaking on condition of anonymity because it has not been announced.
The decision was made by Lt Gen James Kowalski, commander of Air Force Global Strike Command. Kowalski is in charge of all Air Force nuclear weapons, including bombers.