Van Persie, who scored 37 goals for Arsenal in all competitions last season, is set to make his debut in United’s Premier League opener against Everton on Monday.
“Robin is a world-class striker with a proven record in England and in European football,” United manager Alex Ferguson told the club’s website (www.manutd.com).
“His talents need no introduction to our fans – he has scored a number of goals against us in some classic battles with his former club. His movement, finishing and all-round ability are outstanding.”
British media reported that United paid 24 million pounds (US$37.78 million) for the 29-year-old.
“It’s an honour to sign for Manchester United. I am looking forward to following in the footsteps of so many great strikers, bringing my experience and playing my part to help the team compete for the biggest trophies in the game,” Van Persie said. “I can’t wait to get started.”
Van Persie had one year remaining on his deal with Arsenal, who he joined in 2004.
He said in July that he would not be extending his contract with the Londoners because he was unhappy with the direction they were taking.
Arsenal, who finished third in the Premier League last season, have not won a major trophy since the 2005 FA Cup.