Falmouth docks has had its Ministry of Defence contract extended in a deal worth about £80 million.
The MOD has announced it is extending the contract with the A&P Group to maintain its navy support ships for another five years.
A&P Falmouth will continue supporting and maintaining Royal Fleet Auxiliary ships at home and abroad, as it has done since 2008.
Peter Child, managing director, said the contract extension through to June 2018 was confirmation that the Cluster Support Programme partnership with the MOD provided excellent value for money.
He said: "Clustering has achieved a far more economical approach to ship repair and maintenance of the RFA Flotilla through advanced planning, our knowledge of the vessels, our highly skilled workforce and pride of 'ownership' of the ships.
"The cluster programme team has worked very hard on this contract in Falmouth and around the world supporting ships on deployment.
"Extension of this contract reaffirms that A&P can be trusted to meet the very complex needs of our clients and the longer term contract term helps to give A&P Group yards security in our future."
Gerald Pitts, A&P's cluster director, added: "The longevity and continuity of this contract means we can take forward opportunities for innovation and improvement we have identified since being awarded the contract in 2008."