Pietro Piller Cottrer (born 20 December 1974) is an Italian former cross-country skier who won gold medal in the 4 ×10 km relay at the 2006 Winter Olympics in Turin.

In the same year he won the bronze medal with the Italian relay at the 1997 World Championships in Trondheim.

Thanks to Piller Cottrer's presence, the Italian relay confirmed as one of the best in the world winning silver medal in the 2002 Winter Olympics and, better, to gold medal in the home Olympics of Turin.

He also won an Olympic bronze medal in the 15 + 15 km pursuit.

At the 2010 Winter Olympics in Vancouver Piller Cottrer skied a 34:00.9 in the 15 km freestyle event and won the silver medal.