Members of United Voice voted in favour of taking industrial action, the first seen at the casino in 16 years, after negotiations stalled over a new wage deal.
Negotiations for a new enterprise bargaining agreement have been ongoing for six months but the casino and its staff have yet to come to an agreement.
One of the union’s goals in negotiations is to secure stable jobs; it said 70% of Crown’s staff are employed in part-time or casual roles.
A spokesperson for Crown Casino spoke to The Sydney Morning Herald. They said: "We provide a flexible workplace which caters to thousands of staff who prefer to work on a part-time or casual basis.
"Where staff would like to work additional hours, we strive to provide them with the opportunity to increase their hours."
United Voice said roughly half of Crown’s customer-facing employees were members and would be taking part in the strike.
Derby Day, the first major event of the Australian horseracing calendar, is on Saturday and workers will decide on Friday night whether to continue industrial action.
Meanwhile, Crown Resorts CEO John Alexander has denied allegations of money laundering taking place at Crown’s Melbourne casino.
He blamed activists with an "anti-Crown agenda" for releasing the stories.