Trout was the unanimous choice for American League Rookie of the Year in voting by the Baseball Writers' Association of America following one of the best rookie seasons in baseball history.
The outfielder was second in the AL in batting average at .326, while leading the league in steals (49) and runs scored (129).
The 21-year-old also finished third in on-base percentage (.399) and slugging (.564) in pacing the Angels' offense after his April 28 call-up.
Nationals outfielder Harper, only 19 years old, took the NL honors after belting 22 homers, driving in 59 runs and scoring 98 times in helping Washington win an NL East title.
The versatile Harper also stole 18 stolen bases and sported a .817 on-base plus slugging percentage with nine triples.