The value of exports was €1bn higher in May when compared to the previous month, according to the Central Statistics Office.
Total exports during the month stood at almost €7.9bn on a seasonally adjusted basis, according to the figures, 15% higher than in April.
The value of imports was also higher - rising €541m (14%) to more than €4.5bn.
This brought the seasonally adjusted trade surplus to €3.34bn during the month.
Year-on-year, exports were €660m (9%) higher than in May 2013, with organic chemicals seeing a 14% rise and medical and pharmaceutical products up by 12%.
More than half of all exports during the month went to European Union countries, with the US accounting for 23% of all exports.
Meanwhile, 62% of all imports to Ireland originated in the EU, with the US representing 11% and China representing 5%.