More than 800 people are expected to attend various talks, workshops and markets at the Crowne Plaza hotel over the Easter weekend.
It is not the first time Glasgow has hosted such an event, with the massive WorldCon bringing thousands of international sci-fi fans to the city in 2005.
As well as authors and artists, academic scientists have been invited to this year's gathering as organisers look to promote greater links between the fields.
Convention chair Michael Davidson said: "We've held some smaller one and two-day events in Scotland before and had about 200 people attending, so this is much bigger but there are people coming from all over the UK and further afield like America, Russia and there is also a large Scandinavian contingent.
"We've taken the slightly unusual step of having a scientist as our guest of honour because our theme this year is science fiction meets science.
"Dame Jocelyn Bell Burnell, a pre-eminent astro-physicist, is joining us for four days to talk about her work and one of her interests is poetry and space poetry.
"She will be talking about that and how she uses it as a medium to get women interested in scientific careers."
Some attendees at the 65th annual convention have been preparing for months creating hand made models, clothing and jewellery.
Some of the objects on sale for sci-fi and fantasy fans have to be handled with real care.
Anthony Elbert is selling ornamental "dragon eggs" made out of stone with small metal dragons breaking through a crack.
He joked: "One of my specialities is dragon eggs. I'm looking for good homes for freshly hatched dragons until they are ready to return to the wild, it's a conservation project.
"Each one comes with a guarantee - if it doesn't grow in 100 years you can have your money back, I think that's fair."