The man died after heavy rains resulted in an early-morning landslide at a mine belonging to U.S. mining giant Freeport McMoRan, local police said.
"The landslide hit a passing Ford pickup which was driven by an Australian national," provincial police spokesman Wachyono said, AFP reports.
"The car fell about 150 meters down into a ravine. A rescue team is now working to evacuate the body."
A river was at the bottom of the cliff.
The spokesman said the man worked for a Freeport Indonesia contractor.
Freeport mines gold and copper and is the largest single taxpayer to the Indonesian government, ABC reports.
The Jakarta Globe reported that he was a contractor for Redpath Indonesia, though the company has yet to make a statement confirming if this is correct - which it is expected to do later on Tuesday.
Australia's Department of Foreign Affairs and Trade has yet to confirm the man's identity, ABC reports.
Police were still searching the area to determine if others had been swept off the cliff, though police believed this was unlikely.
Last weekend, four Indonesian children were killed in a landslide in a village in Indonesia’s South Sumatra province.
And late last year, 148 people died in flash flooding in Papua.
Papua is the largest and easternmost province of Indonesia.