Nicholas Fitzsimon (1807 – 31 July 1849) was an Irish politician.
Born at Broughall Castle, Fitzsimon attended Trinity College Dublin.
He lived at Castlewood in County Offaly, and worked as a distiller.
He held the seat at the 1835 and 1837 UK general elections, but resigned in 1840 by taking the Chiltern Hundreds.
[2] In 1841, Fitzsimon was appointed as a magistrate in Dublin, and he was knighted later in the year.