The former player is confident the Scot has the ability to turn the club back into title contenders, but described this season as "transitional", before praising Jose Mourinho
Last season's champions currently lie seventh in the Premier League table, 15 points off table-toppers Arsenal, after winning just 12 of their 24 top-flight games this season.
|MAN UNITED LATEST
|14/1||David Moyes is 14/1 with Paddy Power to stay at Man Utd for over 10 years|
"Any season that we're not on top of the league, is a tough season. We, as a Manchester United fan and ex-Manchester United player, we're used to winning championships," Beckham told ESPN.
"We're used to being at the top of the league all the way through the season, so when that doesn't happen, obviously people think, outside of the club, that there's a crisis.
"I don't see it as a crisis. I see it as a transitional period. We win two games, we're in fifth, fourth place. It's simple as that, and then things start looking rosy again."
"I think that David Moyes is a great manager, but it takes time. You know he's joined a club like Manchester United, one of the biggest clubs in the world, and there's a transitional period.
"People talk about it being a tough season. I think the fans believe in Moyes. The fans believe in everything that he believes in. It's just about winning games."
Beckham, though, outlined the strength of United's title rivals, reserving special praise for Chelsea manager Jose Mourinho.
"As a Manchester United fan, I've been watching City and City play some great football," he said. "They're a strong team. They've got a strong unit.
"[Also] there's something about Jose and Chelsea that not many other clubs have. He knows how to win trophies, and he's not just a great manager, he's a strong personality as well.
"There are strong teams there. Arsene Wenger at Arsenal, strong team, great manager, great players. Obviously Liverpool are having a pretty good season as well. Pellegrini I think is a great manager, so we'll see."