Hansjörg Reuter ran his first Junior World Championship in Ridnaun in 2002 . In Italy he was eighth in the sprint, twelfth in the pursuit and won relay gold with Michael Rösch , Robert Wick and Markus Neumaier ahead of the Czech Republic and Belarus. Only a little later at the Junior European Championships of the year in Kontiolahti behind Maxim Tschudow he won silver in the individual, bronze in the pursuit after missing a medal in the sprint in fourth and silver behind with the relay in the Junior World Championship line-up Russia. A year later Reuter won silver again at the Junior World Championships in Kościelisko with the relay, which now included Norbert Schiller and Steve Renner alongside Roesch . In the pursuit, he advanced to seventh after being only 31st in the sprint. In the 2003/04 season, Reuter won two races of the Junior European Cup, including a relay race. The Junior World Championship, which was held in Haute-Maurienne in 2004, was again successful . Here Reuter not only won the gold medal with Renner, Roesch and Christoph Knie in the relay, but also in the individual competition. In addition, he was tenth in the sprint and eighth in the pursuit.
In the senior sector, Reuter made his debut in 2004 as part of the Biathlon European Cups in Obertilliach and finished seventh in his first individual race. If he missed the podium a little later in the same place as sprint fourth, he achieved it in a relay race in the same season in Ridnaun . Reuter won the bronze medal with the relay together with Carsten Pump , Carsten Heymann and Jörn Wollschläger at the European Biathlon Championships 2005 in Novosibirsk . There Renner was also 19th in the sprint and 12th in the pursuit. Reuter has not been used internationally since 2006.