He became world champion in the halfpipe at the 2003 Snowboard World Championships in Kreischberg. He came third in the 2002 World Cup. In 2006 he was Swiss champion in the halfpipe, and in 2002 Swiss champion in freestyle.
On March 14, 2009, Markus Keller took his first World Cup victory. He won the halfpipe event in La Molina in Spain. Thanks to this result, he was also nominated for the 2010 Winter Olympics in Vancouver. Prior to this, he had only ever reached the podium in a World Cup competition in 2004 with a third place in Kreischberg.
In addition to the FIS Tour, he also competes in the Ticket to Ride World Snowboard Tour and won the “Crans Montana Champs Open” slopestyle competition in Switzerland in 2007.
