A Florida man dressed as President Trump allegedly got decked in the jaw by a teenage girl — whose friends filmed the thwacking and posted it on Instagram, officials said.

The costumed victim was waiting in line for the haunted house at the Collier County Fairgrounds with his wife and stepdaughter Saturday around 8:30 p.m., when a 14-year-old girl walked up to him and punched him, authorities said.

Then, “she laughed and ran back to her place in line,” with her four friends, the man told cops, according to a Collier County Sheriff’s office incident report.

The man walked over to the teen and asked why she’d hit him.

“I told her I was with my family here to have a good time,” he said, according to the report.

Deputies said the girl’s “sole motivation was to strike ‘Trump.’ ”

She was booted from the fairgrounds and may be facing a misdemeanor charge of battery, pending an investigation.

A staffer with the Collier County school system told cops that a video of the girl punching the ersatz Trump was posted on Instagram.