Shareena Clanton alleged "multiple racist traumas" during her time on the show in an Instagram post on Monday.
A day later, former Neighbours actor Meyne Wyatt said he too had experienced racism on set in a tweet.
The actors, both Australians of indigenous descent, said they heard other cast members use racist slurs.
"It's been lonely, triggering and traumatising to work in such a culturally unsafe space," wrote Ms Clanton, who has guest starred in yet-to-be-aired episodes of Neighbours.