Ms Johnson was the first woman to fly solo from England to Australia in 1930.
She died when her plane crashed into the Thames Estuary near Herne Bay in January 1941. Searches failed to find her body or the aircraft after she ditched off the Kent coast.
The statue of the pilot, commemorating her at the age of 37, has gone on display on Herne Bay's seafront.
Paul Courtenay, who was Amy Johnson's godson, said: "To be here today to see this wonderful statue unveiled is marvellous. I'm very glad to have been able to come."
Amy Johnson took off alone from Blackpool Airport to deliver an RAF aircraft to Kidlington airbase in Oxfordshire for the Air Transport Auxiliary.
The flight should have taken 90 minutes but, for reasons unknown, her plane ditched in the Thames Estuary four and a half hours after take-off.
Ms Johnson was 100 miles off course and 12 miles off the coast of Herne Bay.
People on boats in the area at the time saw the crash, but were unable to rescue her.
The Herne Bay statue was created by Ramsgate artist Stephen Melton and funded by local people and businesses.
A second bronze statue has been cast for her home city of Hull.
In January, Tracey Curtis-Taylor completed the 14,600-nautical mile flight from the UK to Australia in a vintage open cockpit bi-plane.
She retraced pioneer Amy Johnson's 1930 flight, flying over 23 countries and making some 50 refuelling stops.
Amy Johnson was the first woman in the UK to become an Air Ministry qualified ground engineer in 1929.
She became the first woman to fly solo to Australia, landing in Darwin on 24 May 1930 after 19 and a half days.
In 1931 she became the first pilot to fly from London to Moscow in one day.
In 1932 she flew solo from London to Cape Town in South Africa, breaking her husband's previous record by 11 hours, in .
In 1936 she regained her London to Cape Town record. This was her last long-distance flight.
A bronze statue to honour English aviator Amy Johnson has been unveiled close to where she was last seen alive.