The Chiefs will retire No. 58 on Sunday during halftime of their game with the Denver Broncos at Arrowhead Stadium.
Thomas had completed his 11th NFL season when he died in February 2000 following an automobile crash a month earlier. The nine-time Pro Bowl selection had a franchise-record 126½ career sacks, including an NFL-record seven sacks in one game.
Thomas was inducted into the Pro Football Hall of Fame in August. Representatives of the Hall will make a special presentation to the Thomas family Sunday.