Sir Samuel Pennant (died 1750) was a Lord Mayor of London.
He was appointed a Sheriff of London for 1745 and then elected Lord Mayor of London for 1749 but died the following year in office, and was succeeded by John Blachford. There is a monument to him in the church of St Michael Paternoster Royal.
Sir Samuel's brother John was the father of Richard Pennant, 1st Baron Penrhyn. He was also a distant relative of the Welsh naturalist and antiquarian Thomas Pennant.