Rodolphus (sometimes Robert) Holland Duell (December 20, 1824 – February 11, 1891) was an American lawyer and politician from New York.

Duell was born in Warren, Herkimer County, New York.

Duell was elected as a Republican to the 36th and 37th United States Congresses, holding office from March 4, 1859, to March 3, 1863; during the 37th Congress, he was Chairman of the Committee on Revolutionary Claims.

He resumed the practice of law in Cortland and was Assessor of Internal Revenue for the 23rd District of New York from 1869 to 1871.

Duell was appointed as United States Commissioner of Patents by President Ulysses S. Grant on October 1, 1875, and remained in office until January 30, 1877.