The Argentina international spent three weeks on the sidelines with a hamstring injury before returning as a substitute for the 1-1 Premier League draw at Aston Villa.
Di Maria then suffered a setback when he picked up a knock in training that kept him out of the 3-1 victory over Newcastle United and a goalless draw at Tottenham.
The winger will not feature against Stoke City on New Year's day, but Van Gaal revealed that the 26-year-old is set to return to training.
"He's coming back," said the former Netherlands coach. "I think he shall train with us this week."
When asked if the former Real Madrid star's injury was serious, Van Gaal added: "No, I have said that already."
Third-placed United are 10 points behind leaders Chelsea ahead of their trip to Stoke City on New Year's Day, but Van Gaal has urged his side to concentrate on what they are doing rather than having an eye on their rivals' results.
When asked if United can afford to drop any more points, Van Gaal said: "That depends on Chelsea and Manchester City. They are the only teams who are above us and you have seen Manchester City, in spite of a 2-0 score at half-time, it was 2-2 at the end [against Burnley last Sunday].
"In our last three games - Aston Villa, Newcastle, Tottenham - we should have had nine points in my opinion so you can never predict. You have to always do it by yourself and not depend on results of the other teams.
"You just have to be busy with yourself, with your own preparation and imagination of the game ahead. All the players have to do that - dream of the game. You have to play the game already in your bed."
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