Landertinger debuted in the 2007–08 season, and his big breakthrough came during the 2008–09 season, where he, as of 22 March 2015, has fourteen podium finishes, including a gold medal in the 15 km mass start at the 2009 World Championships in Pyeongchang and a win in the 15 km mass start in Khanty-Mansiysk at the last round of the 2009–10 season. He also finished second in the men's relay in the same World Championships, alongside Daniel Mesotitsch, Simon Eder and Christoph Sumann.