Allen built up her fan base on social networking site MySpace
Lily Allen has branded file-sharing a "disaster", saying it is having a "dangerous effect" on British music.
Writing on her blog, the 24-year-old singer said file-sharing was turning the music industry into "nothing but puppets paid for by Simon Cowell".
"It's making it harder and harder for new acts to emerge," she said.
Last week, an alliance of music stars spoke out against UK government proposals to punish file-sharers in an attempt to crack down on piracy.
The Featured Artists Coalition (FAC) - a new group set up to represent the interests of recording artists that includes members of Radiohead, Pink Floyd and Blur - said "heavy-handed" tactics may turn fans away from music for good.
Referring to FAC and its comments, Allen said: "These guys from huge bands said file-sharing music is fine. It probably is fine for them - they do sell-out arena tours and have the biggest Ferrari collections in the world. For new talent though, file-sharing is a disaster.
"The more difficult it is for new artists to make it, the less new artists you'll see and the more British music will be nothing but puppets paid for by Simon Cowell."
The government is currently considering sanctions against persistent file-sharers, inclusing a proposal to kick them off the internet by suspending their accounts.
Allen added: "The Featured Artists Coalition say that file sharing's 'like a sampler, like taping your mate's music', but mix tapes and recording from the radio are actually very different to the file sharing that happens today.
"Mix tapes were rubbish quality - you bought the real music, because you liked the track and wanted to hear it without the DJ cutting off the end of each song. In digital land pirated tracks are as good quality as bought tracks, so there's not a need to buy for better quality."
Allen built up her fan base sharing her music on social networking site MySpace and blogging updates to her fans.
She praised the site for its ability to stream music and help up-and-coming acts get enough exposure to secure record deals.
The singer admitted there needed to be better ways of purchasing music legally online, but said without fighting piracy "British music is going to suffer".
Blur drummer Dave Rowntree told the BBC last week the FAC was against file-sharing, but "the sensible thing to do is to try to see how we can monetise all this file-sharing activity".
UK Music, an umbrella body representing the British music business, supports the proposals to crack down on file-sharing.
UK Music chief executive Feargal Sharkey said: "We continue to welcome government's support and intervention, both of which will be vital to ensure that those who create and invest in music have the opportunity to deliver their full potential and reap the benefits, rewards and promises of an ever-evolving digital marketplace."