The One Direction star had quit the social networking site on Monday (August 21) because of the "hate" he got from some people.
"Sorry, I was getting some abuse on twitter but I dont want to let my fans down. So I am back!! :) x," he said today (August 23).
He had previously written: "The reason i don't tweet as much as i use to, is because I'm sick of all the useless opinions and hate that i get daily goodbye twitter :)
"My fans that have something nice to say can tweet me on the one direction account , :) x "
In April, 20-year-old Anna Crotti reportedly cancelled a date with Malik due to hate messages online.
His bandmate Louis Tomlinson has also spoken out against web abuse of his girlfriend Hannah Calder.
Harry Styles's alleged ex-girlfriend Lucy Horobin was said to have been forced off Twitter because of abuse from his fans, while Caroline Flack reportedly received death threats when news of her fling with Styles first emerged.