Robert Duff (July 21, 1868–after 1928) was a merchant and politician in Newfoundland.
He represented Carbonear in the Newfoundland House of Assembly from 1924 to 1928.Born in Carbonear, Duff became a prominent business owner in the area.
Duff was president of William Duff & Sons Ltd., the Public Service Electric Co., the Harbour Grace Marine Railway Dock Co.
and the Conception Bay Mutual Marine Co.
He was also a director of the Newfoundland Savings Bank.Duff was elected to the Newfoundland assembly in 1924 as a Liberal-Progressive.
In 1926, he transferred his support to the government of Walter Stanley Monroe and was made a minister without portfolio in the cabinet.He married L.