After playing for England in their 3-2 win over Scotland in midweek, the 27-year-old is included in David Moyes' first Premier League fixture as the Red Devils travel to Wales
The England international, who played over an hour for the Three Lions against Scotland on Wednesday, has seen his pre-season preparations hampered by a series of injuries.
The 27-year-old has been heavily linked with a move to Chelsea this summer, eager to leave Old Trafford after growing frustrated by a lack of starts last term.
But Moyes has given Rooney a clear indication that he still a valued member of the team by including him in the matchday squad against Swansea as last season's Premier League champions begin their title defence.
The former Everton boss makes just two changes from the side that beat Wigan in the Community Shield, with Antonio Valencia picked ahead of Wilfried Zaha and the suspended Rafael replaced by Rio Ferdinand, with Phil Jones deputising at right-back.
Michael Laudrup, meanwhile, started just two new signings for the Capital One Cup winners, Jose Canas and Jonjo Shelvey, with club-record signing Wilfried Bony left on the bench.
Manchester United: De Gea; Jones, Vidic, Ferdinand, Evra; Valencia, Carrick, Cleverley, Giggs; Welbeck, Van Persie. SUBS: Lindegaard, fabio, Smalling, Anderson, Kagawa, Rooney.
Swansea: Vorm; Rangel, Chico, Williams, Davies; Britton, Canas, Shelvey; Dyer, Michu, Routledge. SUBS: Tremmel, Amat, Taylor, Ki, Pozuelo, Hernandez, Bony.