Pat Cox's application to become a member of Fine Gael has been approved by the party.
The former President of the European Parliament had applied to join the party's St Luke's Branch in Cork.
It is widely believed that Mr Cox will seek the Fine Gael nomination for the Presidential election in October.
The 58-year-old served three terms as an MEP for Munster - first with the Progressive Democrats and later as an Independent. He was elected President of the European Parliament in 2002.
MEPs Mairead McGuinness and Gay Mitchell have also stated their intention to run in the election for Fine Gael.