Coinciding with the opening day of the London Film Festival, the broadcaster has upped Film4's budget from £10 million to £15m per annum from 2011 onwards.
The budget increase, which follows a 20% bump in May, is intended to show Channel 4's "deepening commitment" to film and drama as part of its "creative renewal process" launched earlier in the year.
At the Festival, Film4 will showcase five of its new features, starting with Mark Romanek's haunting love story Never Let Me Go starring Keira Knightly and Andrew Garfield, before culminating with Danny Boyle's 127 Hours, the true survival story of mountain climber Aron Ralston.
The division will also show Richard Ayoade's coming-of-age comedy Submarine, gritty drama NEDS (non educated delinquents) and Mike Leigh's Another Year.
"From the opening night film on Channel 4 in 1982, Walter, to tonight's opening night movie at the London Film Festival, Never Let Me Go, Film4 has played a central role in supporting the British film industry and the current team, led by Tessa Ross, has an unrivalled track record of success in developing and supporting British film making," said Channel 4 chief executive David Abraham.
"Film has a special and unique role in UK culture, promoting a wealth of extraordinary British talent from storytellers and producers to directors and actors. I have been determined during the current process of creative renewal to ensure that it plays a commensurate part in Channel 4's public service delivery."
Tessa Ross, controller of Film4 and Channel 4 drama, added: "It's wonderful to be able to deliver some good news to our industry, most importantly because we believe that there is a wealth of great talent here in the UK that this extra money will allow us to support.
"At a time when funding is increasingly difficult to access it will allow us to extend our reach further towards new voices and new audiences."