The Cornwall Museum and Art Gallery (formerly known as the Royal Cornwall Museum) is located in River Street, Truro. It is Cornwall's largest museum of cultural history. Home to over one million objects, its collections of treasures, artefacts, art and photography shine a light on the language, identity and life of this unique region.

It holds an extensive mineral collection rooted in Cornwall's mining and engineering heritage, including much of the mineral collection of Philip Rashleigh. It also maintains a large permanent collection of artworks, paintings and sculptures, etchings and drawings. Besides the renowned art collection, the building houses a library of rare books and manuscripts, and exhibits on ancient civilisations like Egypt and Greece. The museum has a major collection of photographs of Cornwall and a reasonably comprehensive archive of the Isles of Scilly.

The Museum was established in 1818 by the Royal Institution of Cornwall, a learned society dedicated to promoting Cornish arts, sciences and literature. In 2024 it underwent a major transformation, including renaming and renovations, to better showcase its diverse collections and improve accessibility.

The Museum is committed to being family-friendly, with interactive exhibits, activities and facilities for children. It aims to connect with the local community and celebrate Cornwall's unique identity and heritage.