UFO Research (NSW) will host a public forum in Wollongong on Saturday.

Group president Mariana Flynn, a hypnotherapist from Pymble in northern Sydney, said the forum was a chance for people who had "seen anything interesting like a UFO" to share their stories and hear from experts in the field.

She said such sightings were common, but huge social stigma prevented people from broadcasting the details.

"It's actually incredibly demeaning to the person who believes they've seen what they've seen," she said.

"There are thousands of people having these experiences."

Mrs Flynn said the group was contacted two or three times a week by people reporting sightings in the sky from across NSW, and reports had inexplicably increased over the past six months.

A report from Wollongong in August, on the group's website, mentions a descending jet stream with a glowing orange object in front and a glider-type aircraft that passed silently and low, with "six lights in circular pattern flashing like strobe".

Another Wollongong sighting referred to a large, low-lying light over the city that "literally vanished into thin air" in April.

UFO Research (NSW) is based in Sydney but is meeting in Wollongong as part of efforts to branch further afield.

Speakers at Saturday's forum include Ms Flynn, crop circles expert Megan Hazelwood, and Doug Moffett, a former investigator with the group and now its media spokesman.

Mr Moffett said incidents such as the 1980 Rendlesham Forest Event, in England, in which hundreds of American military personnel reported seeing unexplained lights and a landing craft, offered compelling evidence that Earth was being visited by aliens.

"A lot of people see it as a bunch of people in tinfoil hats, going around off their faces," he said.

"If that was true I wouldn't have wasted 20 years of my life on it."

The forum is at the Illawarra Leagues Club on Saturday from 1pm-5pm. Entry $10.