Antetokounmpo won the award in a landslide, receiving 75 first-place votes from a panel of 100 sportswriters and broadcasters and earning 432 points total.
The 2018-19 NBA MVP, Antetokounmpo becomes just the fifth player to win both MVP and Defensive Player of the Year in his career, joining Kevin Garnett, Hakeem Olajuwon, Michael Jordan and David Robinson.
Los Angeles Lakers forward Anthony Davis came in second with 14 first-place votes (200 points), and Utah Jazz center Rudy Gobert, who won the award each of the past two seasons, finished third with six first-place votes (187 points).
Antetokounmpo, 25, anchored the best defensive team in the league in the Bucks, averaging 13.6 rebounds, 1 block and 1 steal in 30.4 minutes per game. Milwaukee allowed only 96.5 points per 100 possessions with Antetokounmpo on the court, giving him the lowest defensive rating among the more than 300 players who averaged at least 15 minutes per game.
According to Second Spectrum, the Bucks superstar held opponents to 36.3% shooting during the regular season, when he was the closest defender. That is the lowest field goal percentage allowed by any player in a season since Second Spectrum started tracking the stat in 2013-14 (minimum 525 field goal attempts).
Antetokounmpo is the presumptive favorite to win MVP again this year. Only Olajuwon (1993-94) and Jordan (1987-88) have won both the MVP and Defensive Player of the Year awards in the same season.
Defensive Player of the Year has been awarded since the 1982-83 season.
The Associated Press contributed to this report.