The S-shaped building will become the focal point of the popular park, which attracts more than 200,000 visitors every year, and lies in the heart of the Thames Gateway regeneration area.
As well as an indoor and outdoor café, the scheme will also house an environmental education centre and new information facilities.
Made from sustainable materials, such as local sweet chestnut, the project will also include a 20kW wind turbine, a biomass boiler and rainwater recycling facilities.
Richard King, Kent County Council's cabinet member for environment and transport, said: 'Kent's countryside is one of its greatest assets and we want to show it off to visitors as best we can at Shorne Wood.
'This centre will have many sustainable features to fit in with the country park's natural surroundings,' he added.
Funded by the council, the ODPM, the Rail Link Countryside Initiative, the Forestry Commission and the South East England Development Agency, the centre is due to open in spring 2006.