Multinationals have an advantage over Irish firms because they pay higher salaries and offer greater benefits, IDA chief executive Martin Shanahan has said.
Supported multinationals added 13,867 net new jobs last year, boosted by expansions at the likes of Facebook, Salesforce and Indeed in Dublin.
That compares to fewer than 5,000 net new jobs added by Irish firms supported by Enterprise Ireland last year.
Such companies are struggling to compete with multinationals in a tight labour market.
"It is true that foreign direct investment jobs are attractive because, on average, they pay well and pay more than average across the domestic economy," Mr Shanahan said.
Figures from the IDA showed foreign direct investment now accounts for 10.5% of jobs in the Republic - twice the level during the Celtic Tiger.
IDA chairman Frank Ryan said the body's founders "could never have conceived of the day when we would have 1,500-plus companies of such calibre from around the world".