"I am sure that Beckham would choose to play at Real Madrid rather than Barcelona," the Real defender told Radio Marca on Wednesday. "They aren't a bad team but we are a more complete outfit."
Beckham looks certain to leave Manchester United before next season and Barcelona are the front runners to sign him after the English champions conditionally accepted a bid this week from presidential candidate Joan Laporta.
The deal to sign the Beckham is far from complete, though, as Laporta has to win Sunday's elections and agree personal terms with the England midfielder before he will be able to bring the
Real Madrid ruled out a bid for Beckham at the end of April, but Roberto Carlos believes that club president Florentino Perez would still be keen to have Beckham playing alongside Ronaldo, Zinedine Zidane and Luis Figo.
"Our president has always gone in search of the best players," said Roberto Carlos. "Let's see what happens in the next few days, but what is certain is that Florentino (Perez) has done enough good work to ensure that Beckham will come to Real Madrid.
"Without doubt he is one of the best players in the world."
Real Madrid are certain of playing in next season's Champions League, while Barcelona face an uphill task to secure a place in the UEFA Cup.