John J. Bradley (1831 in New York City – August 24, 1891 in Mahopac, Putnam County, New York) was an American politician from New York and one of the members of the infamous Tweed Ring.
He ran a large livery yard on the corner of Fourth Avenue and 18th Street. He was a Councilman (57th D.) in 1856, and an Alderman (14th D.) in 1858 and 1859.
He was a member of the New York State Senate (6th D.) in 1862 and 1863.
He was again a member of the New York State Senate (7th D.) from 1868 to 1871, sitting in the 89th, 90th, 91st and 92nd New York State Legislatures.
In April 1870, he succeeded his brother-in-law Peter B. Sweeny as City Chamberlain and County Treasurer, and remained in office until January 6, 1872, when he resigned. Afterwards he resumed his business, and moved the stable to 8 East 31st Street.