US pop star Lizzo has quit the music industry because she is tired of being ridiculed online for her looks and her character.

The About Damn Time singer, whose real name is Melissa Viviane Jefferson, does not make it clear what she is referring to or what sparked the online statement.

However, it comes a day after a lawyer, who represents three former dancers who filed a lawsuit against Lizzo last August, said it was "shameful" the singer headlined a Radio City fundraiser for President Joe Biden "amid such egregious allegations".

"I'm getting tired of putting up with being dragged by everyone in my life and on the internet," Lizzo, 35, said on Instagram.

"All I want is to make music and make people happy and help the world be a little better than how I found it. But I'm starting to feel like the world doesn't want me in it.

"I'm constantly up against lies being told about me for clout & views... being the butt of the joke every single time because of how I look.

"My character being picked apart by people who don't know me and disrespecting my name."

She ended the post saying: "I didn't sign up for this s**t. I quit," with a peace sign emoji.

Last August, Lizzo and her production company were sued by ex-dancers Arianna Davis, Crystal Williams and Noelle Rodriguez, who accused her of sexual harassment and creating a hostile work environment.

At the time, the pop star described the allegations as "gut wrenchingly difficult and overwhelmingly disappointing", adding that the claims are "as unbelievable as they sound".

On Thursday, Lizzo appeared at Radio City Music Hall in New York for a fundraiser for the US president, which Mindy Kaling hosted.