He most notably played in the National Hockey League with the Colorado Avalanche before finishing his professional career with German club Iserlohn Roosters of the Deutsche Eishockey Liga (DEL).
Peltier originally played prep hockey with Robbinsdale Armstrong High School in the Minnesota State High School League and was named in the All-Classic Lake and an All-State Honourable mention by the St. Paul Pioneer Press in 2001–02 before joining the Cedar Rapids RoughRiders of the United States Hockey League.
Posting a career high and team defense best 21 points, Peltier then signed an amateur tryout with Colorado's AHL affiliate, the Lake Erie Monsters, for the end of the 2007–08 season.
Limited to 44 games with Lake Erie through injury, Derek made his season debut for Colorado on January 8, 2010, against the Carolina Hurricanes.
[9] Following a season spent with Rivermen, Peltier left to sign a one-year contract for European team, the Iserlohn Roosters, of the German DEL on June 30, 2011.