Rooney's future has been up in the air ever since Chelsea attempted to prise the 28-year-old away from Old Trafford last summer.
Rooney's current deal is due to expire at the end of next season, but Press Association Sport understands negotiations over a new contract are at an advanced stage.
It is understood that Rooney has almost agreed in principle to extend his contract until the end of the 2018-19 season.
That deal could be signed as early as Wednesday or Thursday.
Rooney is understood to be extremely happy at Old Trafford despite Chelsea's interest in him and United's current predicament.
The reigning champions look unlikely to qualify for the Champions League this year for the first time since the 1995-96 season.
David Moyes' side currently sit 11 points adrift of the top four in seventh position with just 12 matches remaining.
But despite the club's current form, Rooney has enjoyed working under Moyes, with whom he used to work at Everton, and the England striker is said to be content that better times lie ahead.
It is also understood that Rooney could replace the departing Nemanja Vidic as United skipper at the end of the current campaign.
Rooney recently spoke of his desire to break Sir Bobby Charlton's record of 249 goals for United. The England striker's current tally stands at 208.
"It is a great aim for myself to try and get Sir Bobby's record, both at club and international level,' Rooney said.
"It is something which I would like to do. If I can do that I would be really proud because it has stood for a long time."
Rooney joined United from Everton in 2004 for £30million and has gone on to become a firm fans' favourite at the club.
Rooney has scored 11 goals so far this term for United.