City Hall is yukking it up — at the boss.

Just months after Mayor de Blasio launched his presidential campaign, multiple mayoral staffers described an atmosphere of mockery and bafflement at Hizzoner’s bid.

“It’s a joke,” one longtime aide told The Post.

“I think that he knows that he can’t win. It’s just a lot of eye-rolling . . . He’s doing it because he’s got a big ego and needs to prove something, and I don’t think he’s going to quietly go away and become an adjunct professor at Hunter.”

“The look is not great,” said a second, pointing to the mayor’s barnstorming in Iowa during the July 13 Manhattan blackout. “He probably should have come back a little faster.”

The staffer added: “The chances seem so low. If we saw a clear shot for winning or polling higher, I think it would make more sense.”

De Blasio not being around during the blackout also drew criticism from his own party.

City Council speaker Cory Johnson scoffed at the mayor’s absence to The Post. “They say that 90 percent of life is showing up. Well, 100 percent of being an elected official is showing up,” he said.

“I came back,” he added. “I wasn’t in the city. I was on Long Island, and I came back right away.”

Sources close to the mayor suggested they were nevertheless happy to see him on the trail — so they wouldn’t have to deal with de Blasio’s micromanaging and short fuse, they claimed.

One said that during heated moments, he has ordered aides out of his car.

“He’s really not that nice of a guy. He’s always needing to show you how he’s the smartest person in the room,” said the first staffer.

“There is a lot of turnover on staff that interacts directly with him; he’s a difficult guy to work for.”

“He is intense,” offered a third, “but never lost his temper with me.”

The mayor’s emerging national profile also has brought new scrutiny from the national media to city agencies and initiatives.

In March, his wife, Chirlane ­McCray, was widely panned for her performance at a City Council hearing probing the finances of ThriveNYC, the mental-health initiative she founded.

It “invites so much scrutiny on things we have been working really hard on like pre-K, Thrive, closing Rikers and relations with the police,” said the first source.

But the mayor still has loyalists in City Hall, aides who’ve stayed with him during his five years and support his campaign.

“Do I think it’s exciting? Yeah,” said one. “The principal I work for is running for president.”

“The Post camped outside City Hall and called dozens of city workers and the best they could come up with was a story about a few eyerolls. That’s because City Hall continues to deliver for New Yorkers,” said mayoral spokeswoman Freddi Goldstein.