St Blazey (Cornish: Lanndreth) is a small town in Cornwall, England, United Kingdom.
St Blaise is the civil parish in which St Blazey is situated; the name St Blaise is also used by the town council. The village of Biscovey and the settlements of St Blazey Gate, Bodelva and West Par lie within the parish boundaries. An electoral ward also exists in the name of St Blaise. The population at the 2011 census was 4,674.
Once an important engineering centre for the local mine and railway industries, the parish is now dominated by the Eden Project.