Wilfried Cailleau completed his first FIS competition in 2005. On January 13, 2007, he made his debut in Chaux-Neuve in the B-World Cup of Nordic Combined . In a sprint from the normal hill, he finished 27th. He made his debut in the Nordic Combined World Cup a little more than two years later in the same position when he was 38th in a Gundersen competition from the normal hill with a subsequent cross-country distance of ten kilometers.
Between 2006 and 2009 he took part in the Nordic Junior World Ski Championships four times . In 2009 he won the silver medal in the team competition in Štrbské Pleso, Slovakia, together with Geoffrey Lafarge , Samuel Guy and Nicolas Martin . With the same line-up, the French team won a race on February 18, 2012 in the B-World Cup, renamed the Continental Cup in 2008 , which took place in Kranj , Slovenia . In addition, he was able to achieve two podium places in individual competitions in this competition series: on March 12, 2011 in Høydalsmo as second and on December 14, 2012 in Soldier Hollow as third. His best overall result was fourth place in the 2012/13 season .
Wilfried Cailleau competed in his last international competition on March 16, 2014 at the Continental Cup in Kuusamo . He lives in Morzine .