Sustainable Timber Tasmania has been told it will not receive Forest Stewardship Council certification for native forest timber unless it improves in the areas of old-growth logging and threatened species management.
The company failed to receive the valued certification several years ago in these same areas and has worked since to prove to auditors it is worthy of approval.
The company already has FSC certification for its plantation base but not its native timber assets.
Sustainable Timber Tasmania chief executive Steve Whiteley told a government business scrutiny committee on Thursday that a draft audit report had recently been received by the company.
"By virtue of seeing the report in that stage, we understand there are some non-conformances to the standard," he said.
"Until we close out some of those non-conformances, we won't be certified."
Mr Whiteley said the problematic areas regarded old-growth logging and threatened species management.
"We've significantly improved since the last audit ... but because there is a new standard, there are some matters that need to be interpreted," he said.
Mr Whiteley said it may be a case that the company would simply need to provide auditors with more evidence that it could comply with the FSC standards.
The government has a plan to make 365,000 hectares of informally reserved forest into future production forests from next year.
Mr Barnett said he didn't expect opening this land to logging would impact STT's bid for FSC certification.
Greens leader Cassy O'Connor said it was critical Sustainable Timber Tasmania obtained FSC certification for its long-term future.
"This is the certification that global markets are demanding," she said.
Ms O'Connor said the revelation that STT was on-track to again fail to win FSC certification was evidence that native forest logging was not sustainable.
Labor's David O'Byrne said sustainability of timber resources and changes in harvesting methods was important for links to overseas markets.