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 now 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.