John Langdon may refer to:
- John Langdon (politician) (1741–1819), American politician from New Hampshire
- John Langdon (typographer) (born 1946), American typographer known for his ambigrams
- John Langdon Down (1828–1896), doctor
- John Langdon (bishop) (died 1434), English Bishop of Rochester
- John Langdon (driver) (born 1947), New Zealand harness race driver
Famous quotes containing the word john:
“I, John Brown, am now quite certain that the crimes of this guilty land will never be purged away but with Blood.”
—John Brown (1800–1859)