The new restaurant, which will open next week (19 May), will seat up to 110 diners and will be located at the centre's Wintergarden fast food area.
Its launch marks the first of a number of restaurant openings Leon has planned outside of the capital.
Leon co-founder Henry Dimbleby told Caterersearch the Bluewater launch was "major milestone" for the company.
"We're right in the fast food area at the country's biggest shopping centre next to McDonald's and KFC taking them on," he said.
Dimbleby added that Leon has plans to further expand outside of London but said no specific targets had been set.
"The expansion will depend on the property market and on what sites become available. The market is extremely favourable for us at the moment," he said.
Dimbleby denied industry rumours that Leon had plans to list on the London Stock Exchange.
By Kerstin Kühn
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