Pride Toronto co-chair Sean Hillier says there have been a record number of groups registering to take part in WorldPride Toronto and that the "streets are overflowing" with people attending.
The festival kicked off on June 20 and the main event, the pride parade, will take place Sunday.
Hillier says more than 350 groups have signed up to take part in the march along with 12,500 marchers.
He says that this year's annual festival being designated a WorldPride event by a global gay and lesbian group has boosted the number of people attending from abroad, such as more than 400 delegates attending a conference on human rights.
This is the 34th year Toronto has held the gay pride festival.
Ontario Premier Kathleen Wynne, NDP Leader Thomas Mulcair and Liberal Leader Justin Trudeau are all to attend a streetside service by the Metropolitan Community Church of Toronto officiated by an openly gay pastor on Sunday morning
The parade is to start at 1 p.m.