A CNN spokesperson said in a brief statement on Thursday that Hill, a professor of media studies at Temple University, was "no longer under contract".
The network did not give a reason, but the move came amid objections to Hill's speech by the Anti-Defamation League (ADL) and other groups.
Hill had called for "a single secular democratic state for everyone" in a meeting at the UN marking the International Day of Solidarity with the Palestinian People on Wednesday, with a "free Palestine from the river to the sea".
The ADL said the "river to the sea" phrase was code for the destruction of Israel, adding that the annual UN event promoted "divisiveness and hate".
Hill defended his speech in social media posts, saying he did not support anti-Semitism and that his "reference to 'river to the sea' was not a call to destroy anything or anyone".
"It was a call for justice, both in Israel and in the West Bank/Gaza," he tweeted. "The speech very clearly and specifically said those things."
"I support Palestinian freedom. I support Palestinian self-determination. I am deeply critical of Israeli policy and practice," he continued. "I do not support anti-Semitism, killing Jewish people, or any of the other things attributed to my speech."
Source: Al Jazeera