The longest MLB game by innings was on May 1, 1920 between the Brooklyn Dodgers and Boston Braves and lasted 26 innings. The game ended in a 1-1 tie.
This answer is only partly right. The longest game is actually 33 innings played was The Pawtucket Red Sox and Rochester Red Wings, two teams from the triple-A International League, played the
longest game in professional baseball history in 1981 at McCoy Stadium in Pawtucket, Rhode Island.
Not Really. The Pawtucket Red Sox aren't Major league.