NBC Universal News Group chairman Patricia Fili-Krushel announced the cancellation Friday, Politico reported.
"Rock Center," which began airing in 2011, has always had problematic ratings, The New York Times said. The show has also been moved around to five different slots in the schedule and is currently airing at 10 p.m. on Friday.
Williams will continue to anchor NBC's evening newscast.
"I'm so proud of the work we did," Williams said in a statement. "Our people got shot at for this broadcast. They pulled countless all-nighters. They investigated, cajoled, hustled and cared deeply. They won awards, won the respect of their colleagues and produced great television journalism."
With the cancellation of "Rock Center," NBC's only newsmagazine is "Dateline." That show, which began in 1992, has come to focus almost entirely on crime stories.