William Robert Guerin (born November 9, 1970) is an American professional ice hockey player currently playing for the Pittsburgh Penguins of the National Hockey League (NHL). He also played for the New York Islanders.

Bill Guerin has played for the New Jersey Devils, the Edmonton Oilers, the Boston Bruins, Dallas Stars, St. Louis Blues, San Jose Sharks, and the New York Islanders, and was traded to the Pittsburgh Penguins on March 4, 2009 just before the 3:00pm trade deadline.

He has won the Stanley Cup twice, with New Jersey in 1995 and with Pittsburgh in 2009, the World Cup in 1996, a silver medal with Team USA at the 2002 Winter Olympics and was named MVP for the 2001 All-Star game. He was drafted in the 1989 NHL Entry Draft 5th overall by the Devils.