The England captain limped off near the end of Sunday's 3-0 loss at Everton with a knee injury but will be available to face West Brom at Old Trafford on Saturday.
"Rooney is fit to play, it was not so heavy as we expected," Van Gaal told reporters.
Defender Phil Jones and striker Robin van Persie have also recovered from injuries but Luke Shaw and Jonny Evans will not play as United bid to consolidate fourth place in the table.
"Jones is fit but we have to see his match rhythm, but Shaw has trouble with his groin so he cannot play," Van Gaal said.
United have lost their last two games, ending a resurgence in form that took them above champions Manchester City in the race for second place behind runaway leaders Chelsea.
Van Gaal said he had been given three years by the club to bring the Premier League title back to Old Trafford for the first time since 2013.
"The board has given me three years for that objective," Van Gaal said.
"This year we have not challenged Chelsea but we are very close to second position.
"Chelsea are far above the other clubs. Next year it can be different. Next year we shall be better prepared."
West Brom manager Tony Pulis believes Van Gaal will start to feel the pressure next year.
"Louis has obviously spent a bit of money and brought quite a few players in, I think he has had a year to look at it," Pulis said.
"Next year he has to come close to winning the league -- he'll know that.
"It's been great experience for him this year. I'm sure he'll add a few players to the squad next year. They'll want to win it, I see them getting stronger, I can't see them getting weaker."
(Reporting by Ed Osmond; editing by Toby Davis)
Share
