Hunter served four years on the New York Daily News' seven-member editorial board. In 1999, she was a concurrent member of respective news teams that won the Pulitzer Prize and the Polk Award. Prior to that she was the paper’s first African-American female news columnists; she joined the newspaper as a sports writer in 1988, then wrote features and business stories.
In January 2002, Hunter was appointed by the Hunter College administration as an Assistant Visiting Professor in the Department of Film and Media Studies and presently is a Distinguished Lecturer at Hunter College. She also was a morning radio talk show host for three years in New York City.
In 2006, she left her position as a morning talk show host on New York station (1600 AM) WWRL. Her departure followed the dissolution of an early morning team composed of her and WABC personality Steve Malzberg.
In 2007, she launched Karen Hunter Publishing, an imprint of Pocket Books/Simon & Schuster. She has published Why Black Men Love White Women, Faith Under Fire, Love On A Two-Way Street, Recipes for a Good Life with Patti LaBelle, and The Children of Children Keep Coming: An Epic Griotsong with Wall Street pioneer Russell L. Goings. As a writer, Hunter has co-authored five New York Times bestsellers, among them books with Queen Latifah, Al Sharpton, Mason Betha, Karrine Steffans, LL Cool J, Wendy Williams, J. L. King, Donda West, Sandy Denton, Cedric the Entertainer, and Jonathan Plummer.
On January 31, 2007, Hunter appeared on CNN's Paula Zahn Now in a piece on atheists in America. During the open forum portion she made several controversial comments suggesting: "If they [atheists] had Hallmark Cards, maybe they wouldn't feel so left out. We have Christmas cards. We have Kwanzaa cards now. Maybe they need to get some atheist cards and get that whole ball rolling so more people can get involved with what they're doing. I think they need to shut up and let people do what they do."
On April 11, 2011, on her Facebook page, Hunter called for a boycott of the television show Celebrity Apprentice in reactions to comments Donald Trump made about Barack Obama. She said in a later interview: "So many of us were angered and outraged by Trump’s comments and I wanted to let us know that we have power. We can do something besides grumble and complain." 
In 2012, Hunter disparagingly referred on MSNBC to Republican presidential candidate Mitt Romney, remarking: "[M]aybe [Mitt Romney's] not running for the presidency of the United States, maybe he's running for the presidency of 'Caucasia-stan' or some place that doesn't have anyone of color in it." 
In 2015, Hunter wrote a petition on MoveOn.org calling for the removal of the Confederate flag from the South Carolina statehouse following the murder of nine people at a Mother Emmanuel Church in Charleston, SC. Within three days, 500,000 people signed the petition; the second fastest to 500,000 in MoveOn.org's history at the time. Several days later, Gov. Nikki Haley announced that the flag would be removed. This announcement was followed by a vote in the South Carolina state legislature to remove the flag.
It was on The Karen Hunter Show on SiriusXM during the 2016 presidential election cycle where presidential hopeful Dr. Ben Carson revealed that he was held up at gunpoint at a Popeye's chicken "establishment" in Maryland. Carson told Hunter that he redirected the would-be robber to the cashier saying, "You don't want me, you want him." 
- "Karen Hunter". AALBC.Com(The African American Literature Book Club). Retrieved March 31, 2011.
- "Full-Time Faculty | Film & Media". Hunter College. Retrieved 19 March 2013.
- "Karen Hunter". Black Speakers.Com. Retrieved March 31, 2011.
- "Steve Malzberg Joins WWRL 1600 AM" (PDF). October 29, 2004. Retrieved March 31, 2011.
- Karen Hunter author bio
- CNN transcript: Paula Zahn Now: Senator Joe Biden Under Fire Over Controversial Remarks; Has NFL Moved Beyond Racist Past? January 31, 2007
- Sean Yoes (April 13, 2011). "Should Blacks Respond to Trump Birther Stance?". BlackAmericaWeb.com. Retrieved May 11, 2011.
- Frederic Germay (May 9, 2011). "Publishing Magnate, Karen Hunter, Organizes Boycott of "Celebrity Apprentice"". MediaBlvd Magazine. Retrieved May 11, 2011.
- Patriot Post 06June2012 http://patriotpost.us/editions/13731/