The Lynn, Massachusetts native spent three seasons with the Jr. Canadiens before joining the United States National Team in 1967-68 while competing for the US in the 1968 Winter Olympic Games in Gernoble, France.

In 1968-69, Pleau joined the Eastern Hockey League's Jersey Devils where he finished second in team scoring with (81) points while earning EHL North Rookie of the Year honors and was also a member of the 1969 US World Championship team.

While spending the majority of the season with the American Hockey League's Montreal Voyageurs, Pleau did make his NHL debut with the Montreal Canadiens, playing in 20 games and scoring his first NHL goal. Pleau spent the next two seasons with Montreal while playing in eleven games with the AHL's Nova Scotia Voyageurs in 1971-72.

Midway through the 1971-72 season, the World Hockey Association's New England Whalers selected Pleau in the 1972 WHA General Player Draft and during the off-season was claimed by Toronto from Montreal in the 1972 Inter-League Draft.

From 1972-73 to 1978-79 Pleau was a member of the New England Whalers capturing the Avco Cup in 1973 while playing in five games with the AHL's Springfield Indians in 1978-79.

After a successful playing career, Pleau remained in the Whalers organization for 17 seasons as a player, head coach, general manager and minor league general manager and head coach before joining the New York Rangers. Pleau spent eight seasons in New York with the Rangers organization most recently as vice president of player personnel.

During Pleau's three-year tenure as the general manager with St. Louis, he has gained the respect around the league as one of the most progressive thinking general managers in hockey today.

Throughout his career, Larry Pleau has played in 98 NHL games, scoring nine goals while adding 15 assists for 24 points.