The cardboard construction - made from an old microwave box painted yellow - has been placed on the B4396 in Knockin, Shropshire.
Its creator said not enough vehicles observe the 30mph limit on the road.
Although it is not illegal to put up pretend speed cameras, police said they could fall foul of planning laws.
The man who built the camera, who did not wish to give his full name, placed the box on top of a metal post outside his house after he became fed up of speeding motorists.
He said the general consensus from villagers was positive, and he believed the deterrent had been effective.
"The camera will stay as long as it takes to slow people down and get them used to the fact we don't want them speeding through our village," he said.
"It's certainly done the trick and slowed them down," he said.
"There's lots of old people here...people come here too fast, it's dangerous.
"I've spoken to a few people, they all said they're quite happy to see it there.
"I've got a few thumbs up as people have driven past as well."
Warwickshire and West Mercia Safer Roads Partnership said it does not endorse fake cameras and there are rules about how sites are chosen.
It urged communities to raise any speeding-related concerns with their local parish councils or safer neighbourhood teams.
"All of our speed enforcement sites are carefully assessed against strict national Department for Transport criteria around suitability, traffic management and health and safety before being implemented," it said.
A villager who erected a fake speed camera outside his house has vowed to leave it standing - despite criticism from a police road safety group.