The selected practices are 6a architects, Brisac Gonzalez, Urban Salon, de Rijke Marsh Morgan, Fat and S333.
The site, called Offley Works, is owned by the London Development Agency (LDA) and currently consists of six derelict buildings.
The design concepts will be submitted by early April, and will be assessed by a panel of judges, including Design for London, the Architecture Foundation, the LDA, Penoyre and Prasad Architects, and Building Futures.
Peter Bishop, director of Design for London, said: 'I am absolutely delighted that these talented architects are taking part in our competition to design a viable future for Offley Works.
'It is a practical example where Design for London can start to make London a better place for Londoners to live, work and move around in.'
The winning architect and the preferred design concept are expected to be announced by mid-April.