In sport, the First Division is usually the highest division of a league, and will often have promotion and relegation with divisions below. In some cases, the First Division may no longer be the highest division overall in that country, as new leagues can be created above, demoting the First Division down a level.

Examples include:

• The Football League First Division of the English football league system (now only the third highest division)
• The Scottish League First Division of the Scottish football league system
• The Welsh Football League First Division of the Welsh football league system

The term "First division" also has a history of usage in baseball, although the concept of promotion and relegation does not and never has existed in that sport, or in any of the popular team sports in the United States for that matter.

For usage of the term in the military, see 1st Division.