Mayor Bill de Blasio, a self-declared progressive “man of the people,” has erected a massive new “privacy fence” to keep his constituents from looking in on Gracie Mansion.

The new fence — constructed just inside an existing red brick wall and a wrought-iron fence ringing the historic property — was actually dubbed a “privacy fence” by de Blasio and first lady Chirlane McCray, sources told The Post.

“So much for being mayor of the people. That brick fence was good enough for Rudy Giuliani and his family, and for Ed Koch and all the mayors before him,” a law enforcement source said.

“They didn’t need a taller fence. That’s the same house where everybody else lived for years.”

Sources said the increasingly thin-skinned mayor demanded the extension because he was sick of nosy people in Carl Schurz Park peeping in while he hung out in the yard.

“He likes to sit out on the porch and he felt like people were getting too close to him. Some people would see him and yell, ‘Hi, Mr. Mayor!’ ” a source said.

“They weren’t being derogatory or nasty or anything.”

The Parks Department, which maintains the landmarked mansion and added the new fence, would not confirm whether permits were required or ever obtained. The agency also declined to say how much the job cost.

Parks spokesman Phil Abramson claimed the new fence was “due to security concerns.”

The Landmarks Preservation Commission did not return a request for comment about whether the fence needed its approval.

Joni Dropkin, 40, who lives near the Upper East Side mansion, said it was ironic that Hizzoner would build a barrier between the public and his taxpayer-funded home — which is dubbed the “People’s House” in an online visitors guide.

“The fence really turns me off because he always advertised himself as the ‘people’s mayor’ and [said] he would always make himself available. There’s something so shady about it,” she said.

“When he lived in Brooklyn, he was the type of guy who would hang outside and wave to everyone. Now he’s fencing himself in. I wouldn’t mind seeing him on the deck in his robe drinking coffee and waving to the people in the park,” Dropkin said.

“That would show me that he’s not paranoid or afraid to handle the public and issues. That’s the kind of approachable everyman he wanted everyone to think he was when he was getting elected.”

Even wealthy former Mayor Mike Bloomberg, who did not live in the mansion, was easy to spot when hosting public events there, Dropkin added.

“I used to see Bloomberg here in the summer back when he was mayor. You could almost see right in. And that’s what I liked a lot about him; very transparent,” she said.