At a press conference organised by Hansen's current club, Aalborg Håndbold, the 36-year-old said he felt this summer was the right time to step away from the sport, while he was still finding the joy in handball.
Hansen said he had made the decision to retire some time ago, although he still had no plans for what he would do after hanging up his handball jersey.
He said he would like to play at the upcoming Paris 2024 Olympic Games, which Denmark qualified for by winning the 2023 IHF Men's World Championship. Aalborg are also in the quarter-finals of the Machineseeker EHF Champions League, and Aalborg sports director Jan Larsen said at the press conference he hoped Hansen's career could end with a few more trophies - although Hansen is currently recovering from a groin injury.
Hansen began playing handball in his hometown of Helsingør as a junior, joining GOG in 2005 as his first senior club. He then played two years for Barcelona, and another two in Copenhagen, before moving to Paris Saint-Germain in 2012 for 10 years in which he became one of the world's biggest handball stars.
Hansen moved back to Denmark to join Aalborg in 2022, and has played 68 matches for the club, scoring 356 goals to date. He spent part of last season sidelined due to mental health issues.
During his club career, Hansen has won numerous domestic titles and cups, including nine French championships and three Danish championships. In the EHF Champions League, he was runner-up with PSG in 2017 and has reached the EHF FINAL4 another three times, but has never lifted the trophy.