An FDNY lieutenant who was allegedly “highly intoxicated” is accused of taking a swing at Amtrak officers after passing out on the floor in Penn Station, transit cops said.

Lt. Michael Peirano was found in full uniform by a station worker just before 11 p.m. Thursday night lying on the floor in front of the GNC store, preventing them from cleaning the area, Amtrak police said.

Peirano, who officials said was “highly intoxicated,” and had a white substance around his nostrils, got up when approached by Amtrak cops and tried to swing at one of the officers before being taken down to the ground and cuffed, according to Amtrak police

He was taken to Bellevue Hospital for a head injury and was later charged.

The firefighter was slapped with charges of assault on police, resisting arrest, disorderly conduct, obstruction of government administration and trespassing.

FDNY officials suspended Peirano without pay for 28 days following the arrest.