The high-profile liberal rabble-rouser has been under pressure from some progressive groups to run as an alternate to Hillary Clinton, but Warren has resisted jumping in.
During a question-and-answer session at an event called the New Populism Conference hosted by the Campaign for America's Future, the first question from the audience was a request that she run. The questioner hoped that she run as a ticket with Sen. Bernie Sanders, I-Vt., the Senate's only (avowed) socialist. The question drew cheers.
"I appreciate the thought. I am not running for president," Warren said with no hesitation.
She could be heard on the microphone after she left the podium telling AFL-CIO lawyer Damon Silvers, who introduced her, "Nothing can change my mind."
Warren has rejected the idea before, telling ABC last month, "I think Hillary Clinton is terrific. We gotta stay focused on these issues right now."