Krzysztof Miętus starts for KS Start Krokiew Zakopane . He competed in his first jumping competitions since 2006 as part of the FIS Cup . The best result of the first year was a second place in Zakopane . At the Junior World Championships 2007 in Tarvisio he came in 27th place on the normal hill and was sixth in the team competition with the Polish team. For the 2007/08 season he was promoted to the Continental Cup and rarely competed in the FIS Cup. After some good results, about an 18th place on the normal hill in Kranj , Miętus was allowed to debut in Val di Fiemme in the Ski Jumping World Cup in January 2008 , but did not reach the finals in his two competitions. The highlight of the season was the 2008 Junior World Championships in Zakopane. There the Pole could only finish 40th on the normal hill, but won the bronze medal in the team competition on the normal hill with the Polish team behind the Germans and Austrians. After Miętus spent 2008 mainly in the Continental Cup, but rarely made it into the top 20 and never among the top 15, he was allowed to start again in the World Cup in January 2009 in Zakopane. As part of the so-called national group, in which the host nations are allowed to send an extra contingent of jumpers into the competition, he qualified for the finals, where he finished 22nd and collected World Cup points for the first time. He achieved his best World Cup result so far on December 6, 2009 in Lillehammer , Norway , when he finished twelfth.
At the 2010 Winter Olympics in Vancouver , he reached 36th place in jumping from the normal hill and was eliminated after the first round. On August 7, 2010, he won the Grand Prix team competition in Hinterzarten with the Polish team . In September 2011 he was able to jump onto the podium for the first time in an individual from the large hill with second place at the Polish championships. On January 11, 2013, he jumped to second place in the team competition with the Polish team in Zakopane , his home country, and thus achieved his first podium finish in the World Cup.