MySpace will now scan music files on its site
It will use a file-filtering application to scan old and new content to weed out any unauthorised material.
Illegal files, the company said, would be removed and persistent offenders would be banned from the site.
Online sites are coming under increasing pressure from the music industry to stop copyright infringment on their pages.
Last week Google, new owners of video-sharing site YouTube, vowed the company would not tolerate any copyright violations.
MySpace, which reportedly has over 90 million users, is to use technology from a company called Gracenote to review and identify copyright files on its site.
MySpace CEO and co-founder Chris DeWolfe said: "MySpace is staunchly committed to protecting artists' rights, whether those artists are on major labels or are independent acts.
"This is another important step we're taking to ensure artists control the content they create."
MySpace will also soon be allowing unsigned musicians to sell music downloads from their pages. It eventually aims to begin selling copyright-protected songs from major record labels.