Smythies is a surname. Notable people with the surname include:
Bertram Smythies (1912–1999), British forester and ornithologist Charles Smythies (1844–1894), British colonial bishop Evelyn Arthur Smythies (1885–1975), British-Indian forester and philatelist Harriette Smythies (1813-1883), English novelist and poet John Raymond Smythies (1922–2019), British neuropsychiatrist, neuroscientist and neurophilosopher Yorick Smythies (1917–1980), librarian and pupil of philosopher Ludwig Wittgenstein
See also Jill Smythies Award for botanical artists