Will Smith has found a trailer to match his massive ego.

The megastar has docked a gargantuan, double-decker moveable mansion for his “Men in Black III” shoot smack in the middle of SoHo — even though he’s renting a luxury apartment less than a mile away.

Clocking in at 1,150 square feet, the titanic trailer is larger than most two-bedroom, two-bathroom apartments in the city. Rent is $9,000 a week.

CITY TO WILL: MOVE THE TRAILER

The specially designed ride, nicknamed “The Heat,” includes a lounge, a movie room with a 100-inch screen, marble floors throughout, offices for his assistants and writing staff, a large bedroom and all-granite bathroom. It measures about 53 feet long, has 22 wheels and weighs in at around 30 tons.

Neighbors say it seems like the only expense Smith spared was their comfort — with many saying they hope an alien invasion will zap it to smithereens.

“Its ridiculous! I’ve lived here 26 years, and I’ve never seen anything this size,” wailed Myrna Reisman, 62, who lives next to where the trailer was parked yesterday at Broome and Greene streets.

“This thing is like a duplex,” said Reisman. “How would Will Smith feel if I parked that thing out in front of his house? People forget this is a residential neighborhood, not a film lot — that thing is taking up half our gasoline reserve.”

Other locals who live nearby say Smith should think a bit beyond his superstar needs.

“It looks bigger than my apartment!” said Brigette Moreno, 22, who lives above where the trailer was docked yesterday.

“The smell that comes along with it is disgusting. It’s like living in a gas station. I really like Will Smith, but I would be embarrassed if that was my trailer. A little modesty goes a long way.”

And shop owners say the monstrosity is burning a hole in their bottom lines.

“This is killing our business,” moaned Anessa Rahman, the co-owner of nearby Greene Street Antiques.

She said that since the trailer arrived, her business has been a shadow of its usual self.

“We’ve been calling 311, to no avail,” she sighed.

Rahman said the production arrived Monday with around 25 trucks — including a second, 55-foot trailer featuring Smith’s full-sized gym.

The gawdy creation is a product of Anderson Mobile Estates. With the push of a button it can double its height in just 30 seconds and sells for just under $2 million.

Inside, it features a full-service kitchen with arched windows, and matched-grain Italian cherrywood cabinetry.

There’s even a space for Smith to have his makeup and wardrobe done.

A satellite uplink on the roof can send Smith’s movies to and from a 50-inch plasma TV or 37-inch TVs that pop up from cabinets.

The trailer also features a 100-inch roll-down movie screen.

Upstairs holds a lounge with a bar, enough office space for 30 people to hold a meeting, and the mobile offices of Smith’s assistant and his personal writing staff.

The trailer is scheduled to be parked in the same location today, sources said.

In the same neighborhood, Smith is renting a five-bedroom, 6.5-bathroom apartment for $25,000 a month on Bond Street.

“Everything about him is excessive,” said a broker who worked with him.

Initially, his rental budget was $100,000 — a month. He wanted a pool, and he did not want to share an elevator with normal people, the broker said.

City officials said that despite the extra large size of Smith’s trailer, it did not violate any regulations.

“NYPD supervisors and officers assigned to the set from the Movie/TV Unit are on hand to ensure a production’s parking is in compliance with its permit,” said Julianne Cho, an associate commissioner of the Mayor’s Office of Film, Theatre and Broadcasting.

A rep for the studio producing the film, Sony Pictures Entertainment, said, “We know we are guests in the neighborhoods where we film, and are always respectful of the area residents and businesses.”

Additional reporting by Jennifer Gould Keil