Hundreds of staff at KFC, Carl's Jr and Pizza Hut are to strike this weekend amid an ongoing dispute with their employer Restaurant Brands.
The Unite Union members will walk off the job at 2pm this afternoon and won't be back until early Monday morning.
Of the 763 staff who voted over strike action, 88 per cent were in favour.
Union spokesperson Gerard Hehir said the decision to take strike action followed cuts to pay margins and overtime as well as unsafe staffing levels.
He said the strike was particularly extraordinary because it was the first time salaried assistants and store managers are joining the action.
"Over half of them are members of the union to and their offer was less than three per cent, their pay offer, and that's just not good enough," he said.
Mr Hehir said that would put significant pressure on restaurant brands because the managers would be expected to run the stores.
He said the managers and staff especially want better staffing levels inside stores, so they could take breaks and keep their areas clean.
Unite Union said Restaurant Brands made over $36 million last year, and so should be able to afford to pay front-line staff fairly.