The American Idol judges - who were involved in an explosive argument recently during which the Starships rapper screamed violent insults at Mariah because she made her feel "inadequate" during the auditions round of the competition - are said to have buried the hatchet.
The chart rivals were reportedly civil and professional throughout Wednesday's auditions for the reality TV singing competition in Charlotte, North Carolina, according to US gossip website TMZ.
A source told the site that everyone working on the popular series was "shocked" and "embarrassed" by the outburst, which hit the internet after being caught on camera.
Producers were forced to call filming to a halt earlier this week after the judges' disagreement over a contestant turned into a bitter screaming match as Nicki hurled insults at Mariah, calling her "boring as f**k" and threatening "off with your head!".
News of their reconciliation follows reports that Touch My Body singer Mariah was eager to put the spat behind her after handling it with "poise and grace".
A friend of Mariah's said: "She's not going to let this faze her now - the outbursts won't faze her. She'll handle [it] with poise and grace. Mariah has dealt with far worse in her career."
Mariah's husband Nick Cannon - with whom she has 17-month-old twins Morrocan and Monroe - insisted the pop star doesn't want to be caught up in any dramas on the show and is focused on finding the next big singer.