Sir Justinian Isham, 2nd Baronet (1610 – 2 March 1675) was an English scholar and royalist politician.

[2][5] He died at Oxford, on 2 March 1675, and is buried in the family burial place on the north side of the chancel in Lamport Church, where there is a Latin inscription to his memory.

[2] He was only son of Sir John Isham (1582–1651), by his wife Judith, daughter of William Lewin, of Otterden, Kent.

When he was baptised on 3 February 1610, he took his Christian name from his mother's brother, Sir Justinian Lewin, knt.

[2][6] Isham was married on 16 November 1634 to Jane, eldest daughter of Sir John Garrard, baronet, of Lamer, Hertfordshire; but his wife died in childbirth on 4 March 1638.