Devastated workers have lost their jobs and a building site has been abandoned after a major central Queensland building company went into administration.

Administrators have confirmed that JM Kelly Group has gone into voluntary administration and eight of its sub-companies are being liquidated.

Master Builders Queensland regional manager Dennis Bryant described the news as "a devastating blow".

"The worst part about it is that we have 230 employees out of work including 40 apprentices — all locals in the community."

The Rockhampton-based company had 230 workers and had built major government projects in its six decades of business, including the city's Riverside project and a local gallery.

Devastated workers hired under the group's sub-companies told the ABC they had received calls from management this morning.

They were told they no longer had jobs, and to pack up and go home.

Some workers were seen leaving the company's Rockhampton headquarters with packed boxes around lunchtime.

Tradesmen working on a JM Kelly project building a major supermarket also downed tools this morning, and the site has now been locked up.

Some workers held sombre farewell drinks at a nearby pub, and the company's website has been taken down.

What went wrong?

Work has stopped on a supermarket being built by the central Queensland company in Rockhampton. ( ABC News: Chris Davies )

JM Kelly Group is headed up by John Murphy.

In a statement, the Queensland Building and Construction Commission (QBCC) said it had first taken legal action to strip Mr Murphy of his building licence in 2016, following the liquidation of another building company he had been general manager of.

The QBCC and Mr Murphy have been engaged in legal action in court until recently, with the result in Mr Murphy's favour.

In a statement today, Mr Murphy said, despite that win, the court battle had taken its toll on JM Kelly Group.

He claimed the action had meant the company had been removed from certain government tender lists and it had lost opportunities to bid for $90 million worth of work.

"The past few years have been very difficult and trying for all of us at JMK," he said.

"The efforts to defend our business have had a considerable impact on us."

QBCC commissioner Brett Bassett said it would again seek to ban Mr Murphy from the building industry.

"In light of today's developments, the QBCC will again take exclusion action against Mr Murphy, as it is required to do by our legislation."

Sub-contractors not expecting to see money

The QBCC said, since 2015, it had received complaints from JM Kelly Group's sub-contractors about unpaid bills totalling more than $2 million.

It said it had managed to claw back about $680,000 of those debts on behalf of sub-contractors and suppliers.

One small sub-contractor who did drilling work for the company on local government projects said they did not expect to ever see money owed to them.

CQ Drilling office manager Marie Franks said it had been an ongoing battle to get invoices paid, and the flow-on effects were insurmountable.

"They would get us in to do a heap of work and then not pay us for work. It was a battle," Ms Franks said.

"So it's a relief we don't have to do that anymore.

"It's really hard. We're waiting on those funds to pay our suppliers. It's really hard on small business."

JM Kelly Group's woes follow the collapse of another central Queensland builder earlier this year — Metro Homes — which left people with half-built homes.

A smaller central Queensland building company, Metro Homes, collapsed earlier this year, leaving homes half built. ( Supplied: Luke Renshaw )

Ms Frank said she did not think there was enough work going in central Queensland to absorb all the workers who had lost their jobs.

"It's a bit scary," she said.

"Hopefully the industry can pick up what they can, but not everybody is going to get a job out of this.

"It's terrible, especially for families. Such a shame."

The group's administrator PwC hopes to meet with creditors within the week.

In a statement, PwC said it would be conducting "an urgent review" to ascertain whether two companies under the group could continue trading.