Gardaí arrested 18 people last year on suspicion of involvement in Islamic terrorism.
Seventeen of those arrested were detained on suspicion of financing terrorist activities outside Europe.
Investigations remain ongoing by gardaí into lone individual suspects and groups which include both men and women who are either Irish, foreign or hold dual nationalities.
The funds were obtained by these individuals through both legal and illegal methods. The funds were then transferred to countries such as Turkey and Afghanistan.
The number of arrests that have been made in Ireland regarding Islamic terrorism has increased as opposed to other countries across Europe where it has decreased by 41%.
It is not known how many of the arrested suspected have been charged with an offence.
The figures, which were previously unpublished, were contained in the latest European Union Terrorism Situation and Trend report released by Europol. Gardaí told Europol that a small number of foreign terrorist fighters who either fought alongside Islamic State or against them are present in Ireland.
The report added that one fighter who is returning to Ireland from Syria has remained under investigation.