Rooney scored two stunning free-kicks and a penalty as the champions turned on the style to overtake neighbours Manchester City at the top of the Barclays Premier League.
Ashley Young netted two superb strikes with the other home goals coming from Danny Welbeck, Nani and Park Ji-sung.
Robin van Persie missed a penalty for Arsenal who had Carl Jenkinson sent off late on. Theo Walcott and Van Persie grabbed the consolation goals for the Gunners who have now not  won in six Barclays Premier League matches.
It was the first time Arsenal had conceded eight goals in a league match since 1896.
For an in-depth match report, click here.