Work will begin this month on multimedia office and production space blocks to be finished at the end of next year. Around 25,000 square feet space will then be available.
A consortium, including Fragile Films and Manhattan Loft Corporation purchased the Ealing Studios in West London in 2000.
The Studio, built over four acres in West London, is made up of the sound stages, in which the Ealing comedies were made, and a range of workshops and offices, principally dating back to the 30s.
The first phase of construction, three stylish buildings of 33,500 square feet, was completed in 2003, with more than 20 film, post-production, animation, broadcast, music and other media companies now making Ealing Studios their permanent home.
Barnaby Thompson, Head of Ealing Studio, said, "The new space will enable us to continue to expand the fast growing creative community here at Ealing Studios."
The studio's most recent work includes last year's CGI feature Valiant.
Next year sees releases of Fade to Black and comedy I Want Candy.
Ealing is shortly to begin production on St Trinian's to star Rupert Everett.