Mutley Plain is a street in Plymouth, Devon, England. Although Mutley Plain is the main street of the dense suburb called Mutley, the term is often applied to the whole area. The road is a busy dual-carriageway, the B3250, with eight sets of traffic lights/pelican crossings. It was built as a smart tree-lined avenue in late Victorian times and improved over the next half century as a local shopping place for its neighbourhood and the affluent area to the north.