Stannifer has submitted plans to Harlow District Council to extend the Harvey Centre by almost 50 per cent, creating a 75,000 sq m retail attraction and a new department store.
The shopping centre already accounts for nearly three-quarters of Harlow's central retail floorspace.
The Stratford upon Avon-based developer is managing the project for the Sapphire consortium, which includes Bank of Scotland Corporate Banking and South African investment company Corovest.
It plans to extend the existing Harvey Centre by adding a further 23,225 sq m, including the full-range department store. Talks with a potential operator are under way.
The existing space will also be refurbished and reconfigured to provide up-to-date units for high street retailers.
Stannifer chief executive Ron Barrott said: 'Our plans for the redevelopment and refurbishment of the Harvey Centre have met an enthusiastic response from Harlow District Council and retailers alike, all of whom recognise the potential of Harlow's town centre to develop as a regional shopping hub.'
The letting agent for the Harvey Centre is King Sturge.
The refurbishment will help the scheme to maintain its status in the face of competition from Wilson Bowden's£70 million Water Gardens retail and leisure development, the first phase of which is due to open in the summer.
Lettings have already been agreed with Next, Clarks, JD Sports and TK Maxx, while Asda will anchor the second phase.