New figures from the Central Statistics Office show that the seasonally adjusted trade surplus rose by 12% to €4.106 billion in March from €3.667 billion the previous month.
The trade surplus had hit a record-high level of €4.796 billion in January.
The CSO said that seasonally adjusted exports fell by 2% to €8.571 billion in March, while imports sank 12% to €4.465 billion.
Today's figures show that exports of medical and pharmaceutical products decreased by 11% to €2.369 billion, while exports of office machines and automatic data processing machines declined by 16% to €374m.
But exports of electrical machinery, apparatus and appliances jumped by 125% to €574m in March compared to the same time last year.
Meanwhile, imports of organic chemicals fell by 26% to €286m while imports of machinery specialised for particular industries dropped by 65% to €112m. But imports of road vehicles rose by 11% to €356m in March 2016 compared to March 2015.
Commenting on the CSO figures, Merrion economist Alan McQuaid said that the country's trade performance in 2015 benefitted from competitiveness gains made against its main partners and by the weakening of the euro, particularly against sterling and the dollar.
"However, with sterling starting to weaken against the euro on Brexit fears and a less favourable Bank of England interest-rate outlook, that could weigh negatively on Irish exports to the UK in 2016," the economist cautioned.
But despite concerns over trade with the UK, Merrion still thinks the overall merchandise goods surplus this year will be higher than in 2015.
"Following these latest figures, we are now projecting a positive trade balance for 2016 of €44-45 billion," Mr McQuaid said.