Pierre Rioux was born February 1, 1962 in Quebec, Quebec. A former player with the Ste-Foy Gouverneurs of the Quebec Amateur Athletic Association, Rioux joined the Shawinigan Cataractes of the Quebec Major Junior Hockey League in 1979-80 where he spent three seasons before making his NHL debut during the 1982-83 season.
After seasons of 74 and 130 points, Pierre Rioux returned to Shawinigan for his third season of junior hockey where he was a QMJHL First Team All-Star and a member of Canada's gold medal winning team at the 1982 World Junior Championships.
In the summer of 1982, the Calgary Flames signed Pierre Rioux as a free agent. Although he spent the majority of the 1982-83 season with the Colorado Flames of the Central Hockey League, Rioux played well enough to earn a call up to Calgary, playing in 14 games with the Flames.
Rioux was a CHL Second Team All-Star in 1984 after an 83-point season in Colorado with the Flames. The 1984-85 season saw Rioux join the Moncton Golden Flames of the American Hockey League, where he led his team in scoring and was AHL First Team All-Star.
After only eleven games into the 1985-86 AHL season split between Moncton and the Binghamton Whalers, Pierre Rioux headed to Switzerland before ending up in Germany for the 1987-88 season where he finished the season with 145 points.
Pierre Rioux found himself in Finland in 1986-87, before he decided to return to Germany for the next 12 years. Rioux played for seven teams while in Germany, before returning to North America in 2000-01 to play for the St.-Georges-de-Beauce Garaga in the Quebec Semi-Pro Hockey League.
In 14 career NHL games, Pierre Rioux accounted for one goal and two assists for three career points.