The pair were injured in Saturday's win at Aston Villa - which all-but assured Chelsea of Champions League football next term - and underwent scans, but the results will not be made public by the Blues to avoid giving Benfica an advantage.
Rafael Benitez may choose to reveal the extent of the injuries in his eve-of-match press conference at the Amsterdam ArenA on Tuesday, but he may also wish to keep the Portuguese outfit guessing as Chelsea bid to end a second successive season with a European trophy.
Terry was carried from the field on a stretcher after a knock to the ankle, while Hazard finished the game nursing a hamstring complaint. The Belgian had only recently recovered from a calf knock.
Terry has been in and out of the side of late and may not have been selected, but any loss of Hazard would be a blow as the former Lille forward has blossomed this season.
Speaking after the match at Villa Park, won 2-1 as Frank Lampard scored twice to break the Blues' club goalscoring record, Benitez said: "That's the bad news today, the two injuries.
"Both players are injured - Terry and Hazard. We don't know (if they will be fit for the final), we will wait for the scans."
Meanwhile, UEFA has announced Dutch official Bjorn Kuipers will referee Wednesday's match at the Amsterdam ArenA.