It doesn’t matter how big you are, it doesn’t matter how small you are — you only get one seat on the subway.

Police arrested a 4-foot-2 man early yesterday for hogging an extra seat — although the subway car was nearly deserted.

Frank Caldwell, 43, who suffers from a bone ailment, said he was comfortably resting on the 2 a.m. trip home from visiting a friend in Queens, when officers on the F line’s Jay Street platform spotted him.

“I wasn’t even drunk!” he said leaving Brooklyn court yesterday. “They just needed to make an arrest.

“I’ve got a disability in my legs and I just wanted to lie down,” he told The Post.

The officers asked him to step off the train, and a search on his name revealed four outstanding warrants for open containers of alcohol in public, his lawyer said.

But Caldwell said even the cops thought it was a bogus bust.

“One of the officers told me later, ‘If my supervisor weren’t around, I would have just tapped you on the foot,’ ” Caldwell claimed.

A Brooklyn judge told the diminutive subway lounger the charges will be dropped if he stays out of trouble for six months.

The NYPD has been on the hunt for early-morning subway seat hogs. The Post has reported on three such incidents since December.

Additional reporting by Tom Namako and Lorena Mongelli