Others suffered varying degrees of burns and were taken to various hospitals for treatment.
Police are investigating what caused the fiery and destructive explosion, which has devastated the small community of about 900.
There are unconfirmed reports the man driving the four-wheel drive had a heart attack before driving through the front of the building.
Witnesses reported hearing three huge bangs and seeing people running from the cafe on fire.
Alexandra Taylor, who works across the road, told the Cairns Post onlookers were "drenching people" with water to treat victims until paramedics arrived.
Kate Lewis, who works in a supermarket opposite the cafe, said it was "an absolutely horrific scene".
"We just heard a massive sonic boom and went running out and saw the cafe on fire and lots of burnt people," she told the ABC.
Nearby business owner Bert Wilson said there were ambulances and stretchers "everywhere".
"I believe that somebody was seen running out of the cafe on fire," he said.
Bob Katter, whose electorate includes Ravenshoe, described the incident as tragic and praised emergency services for their response.
"We praise the emergency services for having got up there as quickly as they have," Mr Katter said in a statement.
"We stand ready to provide any back up that may be necessary from the federal parliament.
"We wait for more information as it becomes available and pray for all of those involved."
Forensic Crash Unit and crime officers are investigating the cause of the crash.
- AAP
