The so-called Webcameron will feature a blog and regular updates from Cameron, as well as contributions from guests.
An Open Blog section will provide a shared space for users to write blog posts, add images and upload video and audio files.
"Welcome to webcameron. Watch out BBC and ITV - we're coming after you," Cameron said in an introductory video which shows him washing up at the sink. During the piece, Cameron is constantly interrupted by a screaming child.
"This is a really good way of communicating directly with people about what the Conservative Party is doing," he said.
"We can give you behind-the-scenes access so you can actually see what policies we're developing, the things we're doing and have that direct link, because I'm really keen that we can communicate with people properly."
Explaining his motivation for launching the site, Cameron said in a statement: "I really enjoyed the experience of blogging while in India recently and I'm very excited about being able to continue it with this site.
"I hope that the readers find it a fresh and interesting way of getting involved in politics.
"The web has brought about a massive cultural change away from top-down communication and towards bottom-up collaboration where everyone is on the same level. I think it's vital for politics to be part of this change."
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