The Premier League champions outclassed the surprise FA Cup winners in the traditional English season curtain-raiser to give their new manager David Moyes an early trophy in his reign at Old Trafford.
Van Persie powered home an angled header after six minutes and fired in a deflected shot just before the hour to see off Championship side Wigan who stunned Manchester City to win the Cup before being relegated last season.
"It is always nice to score, especially at Wembley," the prolific Dutch striker told the crowd. "I am ready glad for everyone.
"Last year I did not score too many headers, so I have to improve on that. I believe in this team, we are the champions."
Moyes will not be carried away at the start of his bid to emulate the glittering United career of his predecessor Alex Ferguson but he had reasons to be pleased after an indifferent pre-season.
United started brightly and took the lead when Patrice Evra swung over a deep cross from the left and Van Persie arched his back to nod the ball firmly into the far corner of the net from 10 metres out.
United right back Rafael limped off soon afterwards but Moyes's team continued to dominate possession and new winger Wilfried Zaha showed glimpses of his potential with a few quick turns and mazy dribbles.
Man-of-the-match Michael Carrick pulled the strings for United in midfield alongside 39-year-old Ryan Giggs and Wigan struggled to retain the ball.
An error by United defender Chris Smalling just before halftime allowed Wigan's James McClean to send in a dangerous cross but goalkeeper David de Gea did not have a save to make.
Wigan worked tirelessly to close down United but Van Persie's second goal ended the match as a contest.
The Dutchman controlled the ball on the corner of the penalty area before cutting back inside to drill in a fierce, 20-metre shot which took a deflection before flying past Wigan keeper Scott Carson.
Both managers made a raft of substitutions as the hot conditions took their toll and United could have extended their lead in the closing stages.
Van Persie had words of encouragement for those United supporters concerned about Ferguson's departure, Moyes's failure to make major signings and the future of disaffected striker Wayne Rooney.
"We have a chance to win five trophies this year and we want then all," said the forward who scored 30 goals for United last season after joining from Arsenal.
(Editing by Clare Fallon)
