Bernabeu side recover from going down to an early Neymar goal.
Real Madrid come from behind to defeat Catalan opponents.
Barcelona looked to be in dominant mood as they rushed into an early lead at the Bernabeu, with Neymar firing home afer a good cross field ball from debutant Luis Suarez.
The game was played at a frantic pace and after a few near misses the home side leveled with Cristiano Ronaldo scoring from the spot after Gerard Pique had handled in the box.
Five minutes into the second half and Real Madrid were ahead as Pepe rose above a static Barcelona defence to head in a corner.
Having already hit the bar and the post Karim Benzema found the back of the net on the hour to put Real Madrid clear and heading for a crucial El Clasico victory.