The Minnesota Democrat was invited to talk about the looming sequester and President Obama's strategy of campaigning around the country in an effort to drive public opinion.
Hannity led the segment by calling Obama "President Panic" and showing clips of two speeches of what Hannity labeled "sequestration scare tactics," backed by classic scary opera music Carmina Burana.
The host asked Ellison if Obama was fear-mongering in order to get his way, and things got ugly almost immediately.
"I mean, you know, quite frankly, you are the worst excuse for a journalist I've ever seen," Ellison replied. "What you just displayed was not journalism, it was yellow journalism."
"It wasn't anything close to trying to tell the American people what's really going on and it's just shocking."
The host and the congressman later sparred when Ellison referred to Hannity as a member of the Republican party, to which Hannity countered he is "a registered Conservative."
Ellison later called Hannity "immoral" for saying "things that aren't true."
Watch the highlights of the interview below, and the full interview (complete with ominous music) after that.