"Does it get any better than this??," the former England captain, who played with Zidane at Real after joining from Manchester United in 2003, declared on Instagram.
"A man that has been the best at a game we all love, taking over of a club that myself and many more people love... Someone with drive, passion and also doesn't accept failure on any level," added Beckham.
"Taking over from a manager that has huge experience and respect in the game, but taking on a position that he will relish... THE BEST PERSON FOR THE JOB."
Former Girondins de Bordeaux and France team-mate Bixente Lizarazu hoped that his close friend, promoted from the role of coach of Real's B team, would succeed.
"I am very happy for him because I know he is fully committed to this coaching career now, it’s a life choice," he told French RTL radio.
"Zizou coaching Real Madrid, it makes me think of (former Barcelona coach) Pep Guardiola... it’s the same kind of start for Zizou and I wish he’ll have the same success. He is a very determined person, who does things with passion."
Guardiola, now at Bayern Munich and one of the world's most sought after coaches, won 14 trophies including two Champions League titles in a four-year spell as Barcelona head coach.
He had previously been a loyal servant of the club as both a player and B team coach.
Former Real president Ramon Calderon, who resigned in 2009, struck a discordant note, however.
He warned that Zidane was a gamble and that he might not be given much time to prove himself, with former Real coach Jose Mourinho potentially available after his sacking by Chelsea last month.
"I wish Zidane all the best but it will be difficult. If he is not successful then Jose Mourinho will be on the bench in June, I am sure," he told BBC radio.
"He lacks experience as a coach. That is a problem.
"I think the players like Zidane. He won everything with Real Madrid. I am sure the fans will receive him in a very good way. What happens in the next weeks, nobody knows."
Image: Former England player David Beckham (left) with France legend and former Real Madrid team-mate Zinedine Zidane
Photo: Getty Images
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