Kim MacPherson released an annual report that found that the province's net debt is outpacing that of comparable provinces like Nova Scotia, Manitoba and Saskatchewan.
New Brunswick's net debt is up $2.8 billion since 2006-2007 and is expected to soon exceed $10 billion.
"If the province continues in this manner, the financial health of the province will continue to deteriorate," she told the legislature's Crown corporations committee.
"This will have an impact on the province's ability to meet existing financial obligations, both in respect to its service commitments to the public, and financial commitments to creditors, employees and others."
Conservative backbencher Jack Carr, the chairman of the committee, said his government has acknowledged the fiscal situation and is working to correct it.
He said the government has already imposed austerity measures and Finance Minister Blaine Higgs will soon begin pre-budget consultations in a search for more ideas to trim costs.
"The way that things are done today is not sustainable," Carr said.
"In order to protect the programs that we want and our social programs and our health care system and our education system, we have to change the way we're doing things."
MacPherson said so far she hasn't seen the kind of drastic changes needed to correct the fiscal problems.
"Interim 2011-2012 projections indicate a worsening trend," she said. "There are limited signs of the significant changes required to deliver improved fiscal health to the province."
MacPherson declined to suggest the kinds of changes the government could make.
The government is projected to run a deficit of about $546 million for this fiscal year — the fourth consecutive year the province would be in the red.
Liberal finance critic Donald Arseneault said the Tory government's efforts so far are not working.
"You've got ministers who are spending more than what they should or what they're allowed, and the finance minister and the premier don't have control of that," Arseneault said.
"It's a major concern and they're going to have to put their pants on and start making some tough decisions."
The government has made a few moves in recent months in an effort to turn around its finances.
Last month, it announced it was retreating from its 2010 election promise to permanently freeze property tax assessments for seniors. And in November, it said it would seek the Canada Revenue Agency's help to collect from New Brunswickers who owe money to the province.
Premier David Alward has promised his government will return to balanced budgets by 2014.