Sir Robert Marney (ca. 1319-1400), of Layer Marney, Essex, and Kingsey, Buckinghamshire, was a 14th-century English politician. He was the son of Sir William Marney and his wife Katherine Venables.
Marney was a Member of Parliament for Essex in 1369, 1371, 1376, October 1377, 1379, November 1380, October 1382, October 1383, November 1384, 1386, and January 1390. He was a Justice of the Peace for Essex and involved in the suppression of the Peasants' Revolt in 1381.