Saint John or St. John can refer to:
Canada
Jersey
United States of America
- Saint John (North Dakota)
- Saint John (Indiana)
- Saint John (Kansas)
- Parish of St. John the Baptist in Louisiana
- Saint John Plantation in Maine
- Saint John (Missouri)
- Saint John (US Virgin Islands)
- Saint. John (Washington)
Other
- San Ġwann, Malta (also known as Saint John)
- Saint John, river of the Canada
- Saint John, river of the Liberia