Nicholas St. John (by 1526 – 8 November 1589) was an English politician.
The eldest son of Sir John St John of Lydiard Park, Lydiard Tregoze, Wiltshire, he succeeded his father in 1576.
He was a Member (MP) of the Parliament of England for Camelford in March 1553, Saltash in 1555, Cricklade in 1563, Great Bedwyn in 1571 and Marlborough in 1572.
His second son, Oliver, was made Lord Deputy of Ireland and Viscount Grandison.
[1] His eldest daughter Elizabeth married Richard St George.