Bryce Aron Max Harper (born October 16, 1992) is an American professional baseball right fielder and first baseman for the Philadelphia Phillies of Major League Baseball (MLB). He has previously played in MLB for the Washington Nationals.

One of the most heavily touted draft prospects in recent history, Harper has been cited as a "five-tool player." He left Las Vegas High School after his sophomore year so that he could attend the College of Southern Nevada, where he won the 2010 Golden Spikes Award. The Nationals selected Harper as the first overall pick in the 2010 MLB draft. He made his MLB debut with the Nationals on April 28, 2012, at 19 years old. Harper was selected for the 2012 All-Star Game, becoming the youngest position player (19 years, 268 days old on the day of the game) to play in an All-Star Game, and the second youngest overall (pitcher Dwight Gooden was 19 years, 237 days old when he played in the 1984 All-Star Game).

Harper won the National League (NL) Rookie of the Year Award in 2012 and tied for the NL lead in home runs in 2015. He was named the NL Most Valuable Player for 2015 by unanimous decision of the Baseball Writers' Association of America; at age 23, he was the youngest MLB player to win the award. As a free agent during the 2018–19 offseason, he signed a 13-year, $330 million contract with the Phillies, the richest contract in the history of North American sports at the time, which was eclipsed shortly thereafter by Mike Trout, and by several others later on. He won his second NL MVP award in 2021 with the Phillies. The next season, he helped lead the Phillies to their first postseason appearance in 11 years, and was instrumental in helping the team win its first pennant since 2009, winning the NLCS MVP in the process.

Harper attended Las Vegas High School in Las Vegas, Nevada. In May 2009, Sports Illustrated featured Harper in a cover story, comparing him with LeBron James by similarly calling him his sport's "Chosen One". That same spring, he won Baseball America's high school player of the year award. Harper grew up a New York Yankees fan.

Harper dropped out of high school after completing his sophomore year and earned his GED in October 2009, reclassifying and making him eligible earlier for the Major League Baseball (MLB) draft in June 2010.

For the 2010 college season, 17-year-old Harper enrolled at the College of Southern Nevada of the Scenic West Athletic Conference (SWAC) in the National Junior College Athletic Association (NJCAA), where he was a catcher. His older brother Bryan, who had been his teammate at Las Vegas High School, was one of the Southern Nevada Coyotes' starting pitchers, and the brothers often worked as a battery. An advantage for Harper in his eventual transition to his MLB career was that the SWAC, like MLB, uses wooden bats in conference play. In 66 games, he hit 31 home runs with 98 RBIs, hitting .443 with a .526 OBP, and a .987 SLG. Harper's 31 home runs in 2010 broke the school's previous record of 12, and he was named the 2010 SWAC Player of the Year.

In the Western district finals of the 2010 NJCAA World Series, Harper went 6-for-7 with five RBIs and hit for the cycle. The next day, in a doubleheader, he went 2-for-5 with a three-run double in the first game. In the second game, he went 6-for-6 with four home runs, a triple, and a double.

On June 2 that year, Harper was ejected from a National Junior College World Series game by home plate umpire Don Gilmore for disputing a called third strike. Harper drew a line in the dirt with his bat as he left the plate, presumably to show where he thought the pitch was. It was Harper's second ejection of the year and resulted in a two-game suspension. The suspension ended his amateur career, and Southern Nevada lost the game from which Harper was ejected. With Harper suspended, the team also lost their next game, which eliminated them from the tournament. Harper won the 2010 Golden Spikes Award, given to the best amateur baseball player in the nation.