In 1884, New York City's Reservoir Square, at the intersection of 42nd Street and Sixth Avenue, was renamed Bryant Park in his honor. The city later named a public high school in Long Island City, Queens in his honor.
A park in East York, a suburb of Toronto, Canada, bears the name of Cullen Bryant Park as well.
Although he is now thought of as a New Englander, Bryant, for most of his lifetime, was thoroughly a New Yorker — and a very dedicated one at that. He was a major force behind the idea that became Central Park, as well as a leading proponent of creating the Metropolitan Museum of Art. He was one of a group of founders of New York Medical College. He had close affinities with the Hudson River School of art and was an intimate friend of Thomas Cole. He defended immigrants and, at some financial risk to himself, championed the rights of workers to form labor unions.
As a writer, Bryant was an early advocate of American literary nationalism, and his own poetry focusing on nature as a metaphor for truth established a central pattern in the American literary tradition.
Some however, argue that a reassessment is long overdue. It finds great merit in a couple of short stories Bryant wrote while trying to build interest in periodicals he edited. More importantly, it perceives a poet of great technical sophistication who was a progenitor of Walt Whitman, to whom he was a mentor.
Martin Luther King, Jr quoted Bryant in his speech "Give Us the Ballot", when he said, "there is something in this universe which justifies William Cullen Bryant in saying: 'Truth crushed to earth will rise again.'" 
The Seattle neighborhood Bryant is named after him.