Newlyn is a seaside town and fishing port in south-west Cornwall, UK.
Newlyn lies on the shore of Mount's Bay and forms a small conurbation with the neighbouring town of Penzance. It is part of the Penzance civil parish. The principal industry is fishing, although there are also a variety of yachts and pleasure boats in the harbour, as Newlyn has become a popular holiday destination with pubs and restaurants. Although the parish is now listed under Penzance there is an electoral ward in separate existence called Newlyn and Mousehole. The population as of the 2011 census was 4,432.