Sir Dudley Cullum, 3rd Baronet (17 September 1657 – 16 September 1720) was an English Whig Member of Parliament and horticultural author. Dudley Cullum was the son of Sir Thomas Cullum, Bart., of Badmondesfield, Wickhambrook, Suffolk. He was educated in Bury St Edmunds and at St John's College, Cambridge. He succeeded as third Baronet (of Hastede in Suffolk) on 16 October 1680. He was appointed High Sheriff of Suffolk for 1690 and from 1702 to 1705 was Member of Parliament for Suffolk.