List of Major League Baseball single-game home run leaders

In baseball, a home run occurs when the ball is hit in such a way that the batter is able to circle the bases and reach home safely in one play without any errors being committed by the defensive team in the process. In modern baseball the feat is typically achieved by hitting the ball over the outfield fence between the foul poles (or making contact with either foul pole) without first touching the ground, resulting in an automatic home run. There is also the "inside-the-park" home run where the batter reaches home safely while the baseball is in play on the field.

Twenty-one players have hit four home runs in a single Major League Baseball (MLB) game, which writers of Sporting News described as "baseball's greatest single-game accomplishment". The most recent to accomplish the feat to date is Kyle Schwarber with the Philadelphia Phillies against the Atlanta Braves on August 28, 2025. No player has done this more than once in his career. In the pre-professional era, Lipman Pike also hit five home runs in 1866. No player has ever hit four home runs in a postseason game; that record is three, first accomplished by Babe Ruth in Game 4 of the 1926 World Series.