Spanish World Cup winners Xavi and Pedro Rodriguez put Barcelona into a two-goal lead after just 17 minutes and David Villa marked his first Clasico with a brace inside two minutes (54 min, 56) before Jeffren added a late fifth as Mourinho stomached an unforgettable first defeat in charge of Real.
"It was an important win by a big margin and it puts us top two points above Real in the table which is what we wanted," said Villa. "However, it is only November and there are lots of games left and we have to keep on winning."
For Barcelona it was a fifth successive Clasico win over their arch rivals as coach Pep Guardiola maintained his 100 percent record in the fixture and exacted revenge over Mourinho, whose Inter Milan side defeated Barcelona in last season's Champions League semi-finals. Real went into the game unbeaten and hoping for a first win at Camp Nou since December 2007.