Jonathan Bell has been returned as a MLA
The DUP's Jonathan Bell has been selected as a MLA for Strangford to fill the vacancy after the resignation of the party's Iris Robinson.
The move was announced by the Electoral Office for Northern Ireland on Friday.
Mrs Robinson, wife of the NI first minister, resigned her three political positions as an MP, MLA and councillor.
The resignations followed revelations over her private and financial dealings. She officially resigned from the Assembly this week.
On Friday, Mr Bell said: "The DUP has a proven track record of hard work within the constituency.
"And I will be working closely with our three other MLAs in the area to ensure that the people of Strangford continue to receive the benefits which devolution can bring to everyone in Northern Ireland," he said.
The DUP leader, Peter Robinson, said Mr Bell "is a well known local councillor in Ards and he will play a valuable role within the DUP team in the assembly".
Mr Bell has been a DUP councillor in Ards since 2005. He is also a member of the Northern Ireland Human Rights Commission.
He previously sat on Craigavon Borough Council from 1997-2005 serving as both deputy mayor and mayor.
He is a Queen's University graduate in psychology and also holds a Masters degree and a professional diploma in social work.
He works as a senior social worker in the Newtownards area.
Earlier this month, a BBC's Spotlight programme revealed details of Mrs Robinson's financial and personal relationship with Kirk McCambley.
The programme reported that Mrs Robinson sought to provide Mr McCambley with capital to open his business, the Lock Keeper's Inn cafe in south Belfast.
Mrs Robinson obtained a total of £50,000 from two developers, Fred Fraser, now deceased, and Ken Campbell to fund the project.
She failed to register the money at Stormont or Westminster.
She kept £5,000 for her herself and then, when their relationship ended, she demanded Mr McCambley pay the money back.
Mr Campbell has said he contributed between £4,000 and £5,000 to the DUP several years ago.
He said he had never personally donated any money to Mrs Robinson or her DUP leader husband Peter Robinson.
Police in Northern Ireland have launched a criminal investigation into the financial dealings of Mrs Robinson.
When a vacancy arises at Stormont, due to the death or resignation of a MLA who was a member of a political party, no by-election is required.