While playing ice hockey at Burnsville High School, Boeser was drafted first overall by the Sioux City Musketeers in the United States Hockey League. However, he was later traded to the Waterloo Black Hawks in exchange for Cooper Watson. In his first season with the Black Hawks, the 2014–15 season, Boeser led the league with 35 goals and was named to both the 2014–15 USHL All-Rookie Team and First All-Star Team. In 2015–16 Boeser represented Team USA in the IIHF under-20 championships, as the team took bronze overall. During the 2015–16 season playing for the University of North Dakota he was fourth, sixth, and third in goals, assists and points respectively in Division I hockey, the same season he helped the team win the NCAA Division INational Championship. He missed two months of the 2016–17 season due to a wrist injury.
Professional
Boeser was selected 23rd overall by the Vancouver Canucks in the 2015 NHL Entry Draft. He signed a three-year entry-level contract with the Canucks on March 25, 2017. Later that same day, he made his NHL debut in his home state of Minnesota and scored his first NHL goal in the 4–2 win. On November 4, 2017, Boeser scored a hat trick, the first Canucks player age 20 or younger to do so since Trevor Linden on December 20, 1990 as well as the third youngest behind Trevor Linden and Tony Tanti. All three goals came against Matt Murray of the Pittsburgh Penguins, allowing the Canucks to win 4–2. Boeser was named the league's Rookie of the Month for November after leading all skaters with 11 goals in 15 games. He was again named Rookie of the Month for the month of December after scoring 8 goals and 13 points in 13 games. On January 10, 2018, Boeser was named to his first career NHL All-Star Game as a member of the Pacific Division roster. With two goals and an assist in two games, Boeser was named the Most Valuable Player of the 2018 NHL All-Star Game becoming the first rookie to do so since Mario Lemieux in 1985. Boeser also won the 2018 accuracy shooting contest, hitting all five targets in a time of 11.136 seconds. Boeser was injured in a game against the New York Islanders on March 5, 2018, when he collided with Cal Clutterbuck and the Canucks bench. It was later reported he suffered a back injury and would miss 4–6 weeks to recover. At the time of his injury, he led the team in goals, points, shots on goal, and power-play points. Despite missing the final 16 games of the season, Boeser was named a finalist for the Calder Memorial Trophy which is awarded to the league's best rookie of the year. The award was ultimately won by New York Islanders centre Mathew Barzal. Boeser recovered from his injury enough to join the Canucks for the 2018–19 season. He played 13 games and collected 11 points, despite injuring his groin in a game against the Winnipeg Jets on October 18. After missing two games in November due to his groin injury, Boeser was sent back to Vancouver to be examined by a specialist while the team was on a road trip. After being assigned to the injury reserve for 11 games, Boeser was assigned back to the roster on November 27. On December 9, Boeser scored his second career hat-trick, doing so in a 6–1 win over the St. Louis Blues. On September 16, 2019, following the expiry of his entry-level contract after the previous season, Boeser signed a three-year, $17.625 million contract to remain with Vancouver. On October 30, in a 5–3 victory over the Los Angeles Kings, Boeser scored his third career hat-trick. However, his season was cut short in February due to a rib injury that was expected to take him eight weeks to recover.
Boeser, who grew up in Burnsville, Minnesota, is the youngest of three children to Duke and Laurie Boeser; he has a half brother, Paul, and sister, Jessica who has a Developmental disability. Duke was diagnosed with Parkinson's disease in 2010; he would also have a severe brain injury from a car accident a few years later, forcing him to stop working. To help support the family Laurie worked up to three jobs, including serving in a restaurant, office administration, and preparing tax returns. In early August 2014, while Boeser was in Slovakia for the Ivan Hlinka Memorial Tournament, a tragic car accident south of Minneapolis-St. Paul killed one of his closest friends and severely injured another, both fellow students and athletes at Burnsville High School. This followed the death of his grandfather prior to his first game in the USHL.
