Horizon Health is laying off eight front-line employees and eliminating five other positions.
The cuts are to jobs in radiology and nuclear medicine at the Saint John, Fredericton and Moncton hospitals.
New Brunswick Union president Susie Proulx-Daigle says there's been little reason given for the cuts.
"That's all they've told us so far, that they're benchmarking in different areas of the hospital to look at how services are delivered in the hospital, and from their exercise, these are the results," said Proulx-Daigle.
The health authority says patient care will not be affected by the cuts, but Proulx-Daigle says it's inevitable there will be longer wait times.
"We're saying the layoffs, how can it not have an impact on patient care?" she said.
"They're cutting the front-line services, ultimately increasing wait times, so we just don't understand how it cannot affect the system."