Dominic Greyer said organisers of the WI's Centennial Fair in Harrogate asked him to cover up coasters, mugs and tea-towels featuring some of Britain's saucier-named towns and villages.
The author was selling merchandise for his book 'Lesser Spotted Britain' when asked to hide the offending items.
The organisers have yet to comment.
Mr Greyer said he was approached by a male organiser who described some of the promotional material as "unacceptable".
He was asked to put greetings cards in brown paper bags and cover place names with 'censored' stickers.
Mr Greyer said: "It was pretty farcical, it was like I was running an adult shop.
"I had to cover up what on paper seem like rude names but, in context, are real places from around the UK.
"It's just 'Carry On' humour, it's not like you can't drive past these places, they're all out there on the street for people to see."
The writer, from Manchester, said ladies approaching his stall during the event at the weekend were "gobsmacked" by the move and thought it was a marketing gimmick.
"Some of them were pretty put out and thought it was patronising," he added.
Wetwang, East Yorkshire
Cockermouth, Cumbria
Three Cocks, Powys
Twatt, Shetland Islands
Bell End, Northamptonshire
Sandy Balls, Hampshire
Slack Bottom, West Yorkshire
Butts View, Derbyshire
Cocking, Sussex
Bully Hole Bottom, Monmouthshire
Minge Lane, Worcestershire
Assington, Suffolk
Juggs Lane, West Sussex
Furry Way, Cornwall
Rings End, Cambridgeshire
Guests of the event took to Twitter to share their confusion.
"Oh the censorship thing did have us rolling with laughter - we're just so delicate!" said one.
Other WI branches also waded in with their thoughts:
"At the fab @Lesser_Spotted stand at @theWI fair but shocked to find he'd been censored by the MEN who run the event! !" said the Cottonopolis WI.

The red kite was discovered by a member of the public at Daintry Wood near Toddington.
An X-ray image showed it had 10 pieces of lead shot lodged in its body.
The RSPB said: "This was clearly no accident and it is especially sad considering the lengths that have been taken to reintroduce these splendid birds to England."
RSPB inspector Jenny Shelton said: "The bird will most likely have been shot at close range to incur this level of damage.
"Red kites feed mainly on carrion, so there is no logical reason for these birds to be targeted".
Bedfordshire Police has appealed for information about the shooting.
Insp Mark Farrant said: "This is a particularly worrying incident against a bird that is fully protected under the Wildlife and Countryside Act.
"I would ask anyone with information relating to this or similar incidents to call Bedfordshire Police."
According to the RSPB, the shooting of birds of prey is a widespread problem in the UK.
The organisation's latest Bird Crime report said there were 196 reports of shooting, trapping and destruction of birds of prey in 2015, including red kites.
The species is protected under schedule 1 of the Wildlife and Countryside Act 1981 and the punishment for killing one is up to six months in jail and/or a fine of up to Â£5,000.
Red kites became extinct in England in 1871, with only a handful of pairs left in remote parts of central Wales.
The RSPB helped reintroduce them in 1989 and there are now about 1,000 red kites in England.

Howard suffered the injury in a collision with Posh striker Shaquile Coulthirst in Sunday's 1-0 defeat.
The 30-year-old joined Bolton in the summer from Sheffield United and had started every league game so far.
"To lose someone of his quality is a blow for us," manager Phil Parkinson told the club website.
"But it is also an opportunity for Ben Alnwick to stake his claim for a place in the team."
Wetwang, Cockermouth and Bell End were just some of the place names deemed too rude to be shown at a Women's Institute (WI) event.
[NEXT_CONCEPT]
A protected bird of prey has been found dead in Bedfordshire and had likely been shot "at close range".
[NEXT_CONCEPT]
Bolton Wanderers goalkeeper Mark Howard could be out for 12 weeks with a broken thumb and ligament damage suffered in their League One loss at Peterborough.