A "neomasculinist" online group whose supporters believe rape should be legalised on private property and that women are biologically determined to follow the orders of men will meet for the first time in real life in Sydney on Saturday.

The meeting, at 8pm in Hyde Park in Sydney and at 43 other locations around the world, is organised by US-based "neomasculinist" and legal rape advocate, Daryush "Roosh" Valizadeh.

He has said women, transgender men and homosexual men were not invited.

The meetings are being publicised on Valizadeh's news website, Return of Kings, which was established in 2012 and has more than 12,500 Facebook likes and publishes about 15 articles a month.