The Queensland Government is considering legal action against Gold Coast theme park Dreamworld following last year's fatal ride malfunction, which led to the deaths of four people.

Industrial Relations Minister Grace Grace said a Workplace Health and Safety report into the tragedy had finished, but would not be publicly released.

"The report has now been handed over to the WHSQ prosecutions unit to determine the legal consequences of the investigation and the next course of action," Ms Grace said.

"That process is expected to take several months.

"Given the possibility of pending legal action, the investigation report cannot be released at this time."

Floral tributes at Dreamworld at Coomera for the four victims of a ride malfunction on October 25, 2016. ( ABC News: Ashleigh Stevenson )

Cindy Low, Kate Goodchild, her brother Luke Dorsett and his partner Roozbeh Araghi were killed on the Thunder River Rapids ride when their raft collided with another near a large conveyor belt at the end of the ride.

Mr Araghi's father Behrooz, who lives in Canberra, told the ABC that the Government had informed him that the report was finished, but said he would not receive a copy.

"They said they can't release it because they're considering further action," Mr Araghi said.

"I know these things take a long time, two years three years."

He said he could not comment on whether or not Dreamworld should be charged for the death of his son.

"I don't have enough information," Mr Araghi said.

In August, the Government began the process of making "industrial manslaughter" an offence, after an independent review into the Dreamworld tragedy.

However at the time Ms Grace said it was too early to tell if the legislation would be used in relation to the incident.

The theme park has struggled financially in the wake of the deaths, with visitor numbers down 30 per cent for June — a month that included two weeks' of school holidays.