The foursome stormed the stage in an array of silver bodysuits to perform their popular single Shout Out To My Ex.
They certainly oozed confidence as they danced around the stage while belting out the hit.
Unfortunately, many slated the opening number, with one likening it to girls singing in a karaoke booth.
Taking to Twitter, one person tuning in at home wrote: “Don’t get the Little Mix hype. They’re literally just shouting?”
While another added: “@LittleMix @BRITs Yikes girls! Ik you can do better than this.”(sic)
“Little Mix sound like four girls who have got drunk in Tiger Tiger and stumbled into a karaoke booth #screaming #BRITs2017,” a third slammed.
Someone else continued: “They should have added the shouting in the actual single #BRITs2017 #LittleMixBRITs.”
However, the girls did get some support from their fans, with one tweeting: “@BRITs @LittleMix queens slay the brits #BRITVOTELITTLEMIX.”
Their performance came after Little Mix member Jade Thirlwall flashed more than she bargained for when her silver slip dress fell out of place.
The silky number was not held in place tightly enough and as she flaunted her toned pins, it fell to the side and she flashed everything.
Her modesty was barely covered by a strategically placed pad as she chose to forgo underwear for the awards ceremony.
She was joined on the red carpet by her bandmates, Leigh-Anne Pinnock, Jesy Nelson and Perrie Edwards, who all opted for quirky gowns.