O'Keefe tells the network in an interview that the media is a "huge target" of his and he's targeting CNN specifically because it "has a very important role as an arbiter of news."
The network has drawn the ire of President Donald Trump, who has repeatedly labeled it "fake news."
A CNN spokeswoman didn't immediately return a request for comment on O'Keefe's announcement.
O'Keefe became well-known in 2009 after posing as a pimp in a video to embarrass community-organizing group ACORN. He has also made videos targeting National Public Radio and Planned Parenthood.
Some of his efforts have backfired. He was arrested and pleaded guilty in 2010 to entering the office of a Louisiana senator under false pretenses.
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