Major general is a military rank used in many countries. It is derived from the older rank of sergeant major general. In English-speaking countries, when appointed to a field command, a major general is typically in command of a division consisting of around 6,000 to 25,000 troops (several regiments or brigades).

Major general is the highest permanent peacetime rank that can be conferred upon a commissioned officer in the uniformed services (except when General of the Army & General of the Air Force have been authorized and granted by Congress) as higher ranks are technically temporary and linked to specific positions, although virtually all officers promoted to those ranks are approved to retire at their highest earned rank.

Major general (Maj Gen) is a "two-star" rank in the British Army and Royal Marines. The rank was also briefly used by the Royal Air Force for a year and a half, from its creation in April 1918 until August 1919. In the British Army, a major general is the customary rank for the appointment of division commander.