UUP Deputy Speaker David McClarty has been deselected by the party in East Londonderry.
Mr McClarty has been an MLA since 1998.
It is understood former Westminster candidate Lesley Macauley and Coleraine councillor David Harding will fight the Assembly election for the party in May 2011.
In a statement the UUP said the decision had to be ratified by its Executive Committee.
"The selection process is not complete.
"Nominations were sent for consideration to the East Londonderry Elections Committee, which includes representatives from the local association and the central Party Election Committee.
"However, before the process can be considered complete, the nominations which were then put forward by that committee must be approved by the Executive Committee."
© UTV News