"The time for cosmetic changes is gone," he said in his throne speech in the legislature. "We must act firmly and decisively. And we will.
"Real reforms have been put off because this legislature has been divided. What would have been desirable 15 years ago, what would have been necessary 10 years ago, is now urgent."
Couillard said Quebec has 23 per cent of the Canadian population, but contributes only 20 per cent to the national economy.
"In a nutshell, for years we've been spending more than we can afford."
The government's belt-tightening will focus heavily on government program spending.
While Couillard may feel emboldened to act aggressively because of the majority mandate Quebecers gave him in April, he may also run into a reality some of his predecessors have encountered over the years: the strength of the union movement in Quebec.
Couillard got a first-hand look at labour opposition to at least one of his government's plans Wednesday when thousands of municipal workers held a demonstration outside the national assembly.
They were protesting the government's approach to tackling pension shortfalls.
"We want to send a clear message to this new government," said Marc Ranger, a spokesman for the protest organizers.
"If eventually, there's a bill that attacks our rights, there won't just be 10,000 of us here. All municipal workers will be here."
Quebec has the highest debt in the country. As of this past March 31, it was projected to stand at $198.4 billion, or 54.3 per cent of gross domestic product.
Couillard is still gunning for a $1.75-billion deficit this fiscal year before returning to a balanced budget in 2015-16.
"If nothing is done, Quebec's budgetary deficit will be higher than $5 billion in 2014-15 and more than $7 billion in 2015-2106," he told the legislature.
"That will not happen. Our government is still firmly on the road to a balanced budget in 2015-16."