The average salary fell by €249 last year.
New CSO figures show the average person earned €35,830 last year, down from €36,079 the year before- a fall of 0.7%.
But wages in the communications sector are over 15% higher than four years ago - while public sector pay is down over 15% in the same period.
Fianna Fáil's Jobs Spokesman Dara Calleary says wages need to hold steady as more people get back to work.
"It's clear there's employment growth, and we welcome that, but it's employment growth on lower wages," he said.
"Costs aren't coming down - people are going to be paying water charges now … that's going to be an issue.
"Yes, there's a recovery, and I've always accepted that, but is it a real recovery? Is it a fair recovery? And will it be a regionally-spread recovery?"
The CSO also reported that total annual earnings increased by 1.4% to €55.3bn. Earnings in the professional, scientific and technical services grew by 9.9% in that period, while accommodation and food services jumped 10.1%.
However, public sector earnings in health and social work (-0.5), education (-0.8), and public administration (-3.5) all fell during the same period.