Milwaukee Bucks (2012–2018)
On June 28, 2012, Henson was selected with the 14th overall pick in the 2012 NBA draft by the Milwaukee Bucks. On July 10, 2012, he signed his rookie scale contract with the Bucks. On April 10, 2013, he had a season-best game with 17 points, 25 rebounds and seven blocks in a 113–103 loss to the Orlando Magic. A week later, he scored a career-high 28 points in a 95–89 win over the Oklahoma City Thunder.
On October 19, 2013, the Bucks exercised their third-year team option on Henson's rookie scale contract, extending the contract through the 2014–15 season. In 2013–14, he averaged 11.1 points and 7.1 rebounds per game as he came off the bench in 47 of the 70 games he played.
On October 16, 2014, the Bucks exercised their fourth-year team option on Henson's rookie scale contract, extending the contract through the 2015–16 season. Henson played in 67 games for Milwaukee in 2014–15 (11 starts), averaging 7.0 points and 4.7 rebounds per game. He finished fifth in the league for blocks per game with 2.01 and became one of just seven players in Bucks history to average over 2.0 blocks in a single season. Henson blocked at least one shot in 20 straight games from December 26 to February 22, which was the third-longest streak during the 2014–15 season.
On October 2, 2015, Henson signed a four-year, $45 million contract extension with the Bucks. On November 6, 2015, in just his second game of the 2015–16 season, Henson scored a season-high 22 points off the bench in a 99–92 win over the New York Knicks.
On October 29, 2016, Henson hit the game-winning buzzer-beater tip-in against the Brooklyn Nets. In 21 minutes off the bench, he recorded 12 rebounds, seven points, three assists, two steals and two blocks in the 110–108 win. On November 27, 2016, he scored a season-high 20 points in 104–96 win over the Orlando Magic.
On February 4, 2018, Henson had season highs with 19 points and 18 rebounds in a 109–94 win over the Brooklyn Nets.
On November 16, 2018, Henson was ruled out for approximately 12 weeks with a torn left wrist ligament. He underwent surgery on November 28.
