Tony Ferguson, 33, filmed the moment he visited the supposedly haunted former Victorian school at Manor Farm in Bursledon, Hampshire on February 10.
He claimed staff at Manor Farm warned him not to goad the “ghost” as she has been known to spook guests.
But Tony ignored the warning and proceeded to seek out any so-called lingering spirits.
In the video, the investigator is seen standing in an old classroom, before asking: ”If there are any children here can you make a massive banging noise to show us where you are?”
He seems to hear some movement coming from upstairs moments before receiving the shock of his life.
The door behind him proceeds to slam shut – despite a 10kg weight holding it open.
Tony looks visibly shocked and nervously asks: “What the f***?”
After the spooky encounter, he said: “The door had a 10kg weight on the bottom and it was hooked as well, so whatever unhooked it and slammed it with some force.
“It definitely left me shocked.
“The school is supposed to be haunted by one of the teachers who used to work there.
“Apparently the teacher has been seen a couple of times and she doesn’t like people doing her job role for her.”
Tony believed he even spotted the teacher earlier in his visit at the farm, which is located within River Hamble Country Park.
He claims a woman dressed in a Nanny McPhee-style dress walked past him but he thought it was a member of staff in fancy dress.
But after he later spotted a picture on the wall of the same woman, he realised he might have seen an apparition of the former teacher.
He added: “For me that makes it a personal experience where I saw something with the naked eye that didn’t appear on camera but then the door slammed.
“It was her saying ‘yes, you did see me, but get out’.
“I was unsettled because I thought ‘oh God, I’ve p***ed the teacher off!’ and I was wondering what next would happen.
“I got the feeling that we were being followed around and I could tell she didn’t want people in there.
“The teacher is clearly very protective and territorial. She’s a very controlling person from the staff have told me.”
The eerie encounter has not put the keen investigator off as he plans to return to the old school later this year.
A spokesman for Manor Farm requested to view the footage but declined to comment.
It’s not the first time someone has been left horrified by paranormal activity.
Weeks ago a mum was left shocked after re-watching CCTV footage of a “locked gate“.