By the NFL's definition, "questionable" means a player has a 50-50 chance of playing. The fourth-year receiver was limited in practice this week.
Amendola has been out since injuring his collarbone in the Rams' Oct. 4 game against the Arizona Cardinals.
The Rams play the Patriots at Wembley Stadium in London on Sunday. The team flew to London on Monday to get acclimated to their surroundings.
In five games this season, Amendola has caught 32 passes for 395 yards and two touchdowns.
Amendola is coming off a 2011 in which he played just one game because of injury. In 2010, Amendola caught 85 passes for 689 yards and three touchdowns.
Amendola also returns punts and kicks for St. Louis.
Sunday's game is scheduled for 1 p.m. ET.