In confirming Stastny will return, coach Ken Hitchcock said veteran forward Scott Gomez will be a healthy scratch.
Stastny is a six-time 20-goal scorer and been out since he was hurt in the second period of a 4-3 win over Vancouver on Oct. 16. He had a goal and four assists in five games.
The Blues (13-6-2) are still banged up with forwards Jaden Schwartz (broken right ankle) and Patrik Berglund (right shoulder surgery) still out.
For Buffalo, coach Dan Bylsma says forward Zemgus Girgensons will miss his fourth game and is listed as day to day with an upper body injury.