RFA Mounts Bay is one of those that will be maintained at Falmouth
Five hundred shipyard jobs have been secured in Cornwall after the Ministry of Defence agreed a multi-million pound contract with Falmouth Docks.
The A&P group has signed a deal worth £53m at its bases in Falmouth and the Tyne, which could last up to 30 years.
Five Royal Fleet Auxiliary (RFA) vessels will be maintained and refitted in Falmouth.
Bosses said it meant job security for the current workforce and support for about 2,500 jobs locally.
The RFA supplies fuel, munitions, food and other vital ship's stores to the Royal Naval fleet while on operations at sea.
The contracts are a new policy by the MoD to appoint contractors to look after ships for the lifetime of the vessels rather than on a short-term basis.
Baroness Taylor, Minister for Defence Equipment and Support, said: "This is a significant change to the way in which the RFA ships are supported, which will not only generate substantial savings for the public purse but will increase the ships' availability and effectiveness to the fleet they serve."
Peter Child, managing director of A&P Falmouth said: "We are delighted from Falmouth's point of view.
"There are about 1,000 people employed in the docks, of which A&P employ about half."
Trainee engineer Fred Hawkey, who found work at the docks after a succession of short-term jobs, said: "Employment is a bit hit and miss down here.
"You may only get work for the summer so if it means I will have regular work for the foreseeable future that would be good."
Mayor of Falmouth Mike Varney said: "Falmouth docks are a massive part of the town's heritage.
"To secure this work for the next 30 years is wonderful."