Ledger -- a Perth native and the star of "A Knight's Tale," "Brokeback Mountain," "Casanova," "I'm Not There" and the upcoming "The Dark Knight" -- died in January of an accidental prescription drug overdose at the age of 28.
The BBC said Ledger's father Kim attended the naming ceremony for the 575-seat theater.
"I really feel that there's not a lot of things he'd put his name to, but he'd put his name to that," the elder Ledger said.
"Heath Ledger was totally dedicated to the craft of being an actor and that's what made him successful," the BBC quoted politician Alan Carpenter as saying.
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