A massive pooch and its disabled owner can’t get into a swanky Lincoln Square apartment building — because the complex only allows small dogs.

Tatiana Iattcheni and her fiancé, Eduard Gitlin, are suing Glenwood Management for federal rental discrimination after it denied their application to live in the Grand Tier complex, which they claim has a separate “poor door” for subsidized apartment renters.

Iattcheni asked for an exception to the complex’s no-dog policy in 2016, so she and Gitlin could live with Iattcheni’s emotional-support dog, a 120-pound cane corso named Capo.

But Grand Tier said the dog was “enormous,” and feared it would “make other residents uncomfortable,” according to the complaint filed Friday in Manhattan federal court. The complex said the couple could bring a dog only if it was under 50 pounds and could be carried through building common areas.

“Cane Corsos are known for strong temperament, with loud snorts and grunts,” the complex told the couple, according to court papers.

“A large dog in a small apartment cannot lead to good results, either for the dog or the apartment.”

The couple claims the decision violated a host of federal, state and local laws. They are seeking an apartment at the 2016 rate.

Glenwood denies it has any “poor door” buildings. Reps said Saturday that the company is already in settlement negotiations with the couple concerning a separate federal complaint.