The video-on-demand service will initially offer over 300 hours of old and new content from BBC Worldwide and All3Media.
Viewers will be able to watch free episodes of shows including 'The Young Ones', 'Mock The Week', 'Skins', 'What Not To Wear', '10 Years Younger' and 'How To Look Good Naked', as well as factual programmes.
The service is ad-funded and viewers will be shown a 30-second ad at the beginning of each programme and then commercial breaks during the show.
It will be available on Microsoft's MSN site to anyone in the UK with a high-speed internet connection.
If the service proves to be popular, plans to roll it out across its Xbox 360 video game console, Windows Mobile and onto TV screens via Project Canvas -- the joint IPTV proposal from the BBC, ITV, BT and Five.
The launch of MSN Video comes as US video-on-demand site Hulu prepares to launch in the UK in September.
Hulu, owned by Disney, NBC Universal and News Corporation, offers thousands of US TV shows, including 'The Simpsons', as well as movies.
The service is believed to be signing up UK content partners ahead of its launch in Britain.