The National Lighthouse Centre in south Cornwall is to close, owner Trinity House has announced.
The decision follows three years of consultation with Penwith and Penzance town councils.
Trinity House says the lighthouse artefacts need to be displayed at a large centre which has greater public accessibility.
The Penzance museum, opened in 1991, has one of the finest collections of lighthouse equipment in the world.
It has been reported that a new museum in Plymouth could be an option for a new site.