The 1999 World Series was the championship series of Major League Baseball's (MLB) 1999 season. The 95th edition of the World Series, it was a best-of-seven playoff between the defending American League (AL) and World Series champion New York Yankees and the National League (NL) champion Atlanta Braves in a rematch of the 1996 World Series, in which the Yankees prevailed. The Yankees swept the 1999 Series in four games for their second consecutive title, third in four years, and 25th overall. It was the Yankees' third straight defeat of the Braves franchise in the Fall Classic. Yankees closer Mariano Rivera was named the World Series Most Valuable Player. This was the first World Series to feature both #1 seeds from the AL and NL, a phenomenon that has only occurred twice since, in 2013 and 2020.

The Willie Mays World Series Most Valuable Player (MVP) Award is given to the Major League Baseball (MLB) player deemed to have the most impact on his team's performance in the World Series, which is the final round of the MLB postseason. The award was first presented in 1955 as the SPORT Magazine Award, but is now decided during the final game of the Series by a committee of reporters and officials present at the game.