A lease has been agreed for a berth in the Purfleet, in the shadow of the Custom House, where the vessel would be moored.
Suffolk businessman Roger Clarke-Payton hopes to bring a ship to the restored dock beside the tidal Ouse by Easter.
'There is considerable groundswell of support for this proposal from local people, businesses and other residents anxious to put King's Lynn back upon the map for a healthier financial future,' he said.
He added food and drink on offer would be 'at the top-end of the culinary scale, in presentation and service', with an 'interesting selection' of wines.
Mr Clarke-Payton said a business plan has been prepared for investors in the project, who are meeting next week to 'cement the proposal'.
West Norfolk council first announced it would welcome a floating restaurant to Lynn in 2006. Similar ventures operate successfully up the coast at Wells, where the Albatros offers food and drink from her mooring on the Quay; and in Norwich, where Thai on the River operates from a berth on the River Yare.
Silt was removed from King's Lynn's Purfleet almost 20 years ago, so visiting vessels could use it once again, with a lock gate installed to maintain water levels.
But since then just a handful of boats have visited what was once a bustling dock, when West Norfolk council staged maritime festivals in the early 2000s.
West Norfolk council officials advertised the berth for a floating restaurant on Rightmove. Today it confirmed a let had been agreed.
A spokesman added: 'This is great news, and we're sure that a floating restaurant will be a real asset to our historic waterfront. We should emphasise that although a let has been agreed, we are still early on in the process of granting the various permissions that will be required.'
The berth was described as a business opportunity situated within a historic quay, close to the town centre and overlooked by the Custom House and other historic buildings.
'The borough council wish to consider expressions of interest from a business to moor a well preserved vessel of up to 30m (100ft) length to positively impact on the historic importance of the quay area,' the online ad goes on.
'This will encourage interest in the riverside and promote increased attention in the area and King's Lynn as a whole.'
The listing states the 10-year lease is subject to planning permission and other 'statutory consents'.
It says the vessel's operator will be responsible for insurance and must pay a deposit of three months' rent.
Mr Clarke-Payton said: 'The council officers, have been extremely constructive, helpful, enthusiastic and welcoming to the venture and nothing insurmountable is envisaged to this point.'
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