John R. Fellows (July 29, 1832 – December 7, 1896) was an American lawyer and politician from Arkansas and New York.

He ran for presidential elector on the Constitutional Union ticket of Bell and Everett in 1860, but Arkansas was carried by John C. Breckinridge.

After the Battle of Shiloh, he was made a colonel and assigned to staff duties as assistant adjutant to Gen. William Beall.

Urged by Tweed, Fellows removed to New York City to continue the practice of law there and to campaign for the Tammany organization.

During the fiercely fought election campaign, two letters Fellows had written to Boss Tweed on February 1, 1873, asking for a loan of $523, (~$13,302 in 2023) were published in The New York Times, with the comment that this was the payment for Fellows's service in having the jury disagree on a verdict against Tweed on the previous day, and that the "loan" was never paid back.

Fellows was elected as a Democrat to the 52nd and 53rd United States Congresses, serving from March 4, 1891, until his resignation, effective December 31, 1893.

In September 1896, he was a delegate to the National Democratic Convention in Indianapolis which nominated the Palmer - Buckner ticket for the 1896 United States presidential election.

Fellows died on December 7, 1896, at his home at 610, West 152nd Street in New York City from stomach cancer; and was buried at the Trinity Church Cemetery.