Midfielder Bale (hamstring) and defender Gallas (knee) have been ruled out of Saturday's Premier League game at Wigan Athletic and face a battle to play at the Bernabeu on Tuesday.
"Gareth is not fit for tomorrow. William Gallas as well - his knee has been giving him problems so they are both certainly not fit," Redknapp told reporters at the club's training ground.
Asked if Bale will be ready to face Real Madrid, Redknapp said: "We will have to see. His hamstring is still a little bit tight. You never know with those injuries. Until he pushes it we wouldn't be sure. But he looks like he's getting over it.
"He's doing lots of work with the fitness coaches but he hasn't actually joined in (full training). He's working at about 80 percent at the moment." "I wouldn't be sure also with William at the moment (if he will be fit for Tuesday). He can't kick a ball. He feels his knee is sore. He has had two scans this week.
"He has been out this morning and done some running but when he looks to strike the ball he has problems."
Spurs are already without central defenders Ledley King, who needs groin surgery and will miss the rest of the campaign, Jonathan Woodgate (calf) and Younes Kaboul (thigh).
"Ledley is having an operation and is out for the season. He has been out most of the year unfortunately," added Redknapp.
Sebastien Bassong will come into the centre of defence alongside captain Michael Dawson at Wigan with Redknapp stressing the importance of the game as Spurs chase a top-four finish and a place in next season's Champions League.
"We've got to look to get Champions League football for sure next year if we can," he said. "It's a vital game at Wigan."
Tottenham are currently in fifth spot, four points behind Manchester City but with a game in hand.
