A hotshot banker dumped his model girlfriend, and she got the ultimate revenge — by driving his precious Mercedes into the backyard pool, he said.

Russian-born model Kristina Kuchma was furious with Guy Gentile for breaking up with her during a dinner out near his Bahamas home, rather than fund her marketing business venture.

“Lier!” Kuchma, 24, texted Gentile in broken English on Saturday night after the dirty deed. “You told me you will help me to start a business! That were your words! Now you want to be an investor??? Well investor I have a surprise for you on a backyard, start with that investment idea first.”

Gentile, who was busted for an alleged Wall Street pump-and-dump scheme in 2007 but became an FBI informant to beat the charges, came home the next morning to find his Mercedes S400 hybrid in a chlorine grave.

“My heart dropped because of [fears she was inside]. I didn’t care about the car at that moment,” he said. “But after I realized she wasn’t in it, then I start to get pissed off that she would pull something like this after everything I’ve done for her.

“I dumped her. She dumped my car.”

Kuchma declined to comment when reached on her cellphone.

Gentile, who runs a Bahamas-based brokerage, said their last dinner together was supposed to be a casual one with a friend — until she dropped a bomb on him. “She looks at me and says, I have something to tell you,” he said. “I’m pregnant.”

Gentile agreed to support the kid, until she abruptly changed her tune. “I’m not pregnant with a kid — I’m pregnant with an idea,” she told Gentile.

Kuchma wanted to start a marketing business and hoped he would help fund it with a $50,000 gift, he said.

Gentile had already bought her a Gucci bag, a new iPhone, and new Beats headphones as a birthday gift — but this request “blurred the lines” between business and romance, he said.

He decided then to end their year-and-a-half-long relationship.

“I said, ‘You know what? You got the wrong guy. If you want a guy who’s going to hand you money for nothing, you got the wrong guy,’ ” he said.

Kuchma threw hot green tea in his face. “It was really disrespectful to do that at a restaurant I dine at a lot in front of a good friend of mine,” he said.

She then stormed off, taking the keys to his $55,000 ride so she could deliver some payback, he said.

Cops confirmed to The Post that a police report was made. Gentile told police Kuchma was the only other person with access to the car. It took more than four hours to get the car out of the pool, Gentile said. “I really loved this girl and would have married her,” he said, “but she went too far!”