The former One Direction star said he made the decision after the song Zayn x August Alsina - Don't Matter (Remix) was leaked.
The announcement sent fans into a frenzy, with the website where the track was available crashing.
Many shared their frustration at not being able to hear the song, with one commenting: "The link isn't working i'm gonna cry."
And the hashtag #Don'tMatter quickly started trending worldwide.
Malik, 25, tweeted: "This was not a song I intended to put out, but due to unprofessionalism has been leaked by someone and my fans mean more to me than a stupid leak, so here it is free for you to enjoy."
Malik split from One Direction in March 2015.