Scientists have not discovered a firm link between mobile masts and cancer, but residents in Bardsey are determined to stop what they see as an increased risk.
Protestors temporarily stopped erection of the new mast last week when they blocked the entrance to a work access track.
T-mobile, which does not have any other masts in the area, is meeting Leeds City Council on Thursday to press its claims for it to be built.
Health worries
The company say the protests were in response to a planning permission mix-up.
But organiser Geoff Nun told the BBC it was the possible health risks that worried local residents.
"In terms of possible health risks of mobile phones, we may be where we were in the 1950s with regard to cigarette smoking. For 200 years that was thought to be safe," he said.
Resident Nicola Shires, who has a seven-centimetre brain tumour, does not want another mast.
She told the BBC: "They haven't done enough research to prove the link one way or another.
Confidence in safety
"In the village at the moment I know four people who have had brain tumours including myself.
"It all seems to be very localised, which does concern me."
T-mobile spokeswoman Jill Kerr told BBC News Online that they understood villagers' concerns, but said mobile masts were not harmful.
"We work within strict guidelines recognised by the World Health Organisation that are designed to protect the public," she said.
"So we are confident they are safe."