Hushovd's final race will cap 15 years in the peloton that include his world title in 2010, 10 stage wins and two points classification titles at the Tour de France and three Norwegian national road and time trial victories.
"It has been a real pleasure to have Thor be a part of the BMC Racing Team in the twilight of his career," BMC Racing Team President/General Manager Jim Ochowicz said.
"We will not soon forget the impact he has had on the sport, especially in his home country of Norway."
Joining Hushovd on the roster for Saturday's race is Greg Van Avermaet, winner of the Grand Prix de Wallonie on Wednesday.
The BMC Racing Team will also compete Sunday in France in the Grand Prix d'Isbergues.
BMC for Primus Classic Impanis-Van Petegem Roster on September 20:
Luke Davison (Aus), Thor Hushovd (Nor), Martin Kohler (Swi), Sebastian Lander (Den), Michael Schär (Swi), Dylan Teuns (Bel), Greg Van Avermaet (Bel), Rick Zabel (Ger).
BMC for Grand Prix d'Isbergues Roster on September 21:
Luke Davison (Aus), Yannick Eijssen (Bel), Ben Hermans (Bel), Martin Kohler (Swi), Amaël Moinard (Fra), Michael Schär (Swi), Loïc Vliegen (Bel), Rick Zabel (Ger).