Lyth may refer to:
;In people
* Robin Lyth Hudson (born 1940), British mathematician
* Adam Lyth (born 1987), English Test cricketer
* David H. Lyth, researcher in particle cosmology
* Isabel Menzies Lyth (1917–2008), British psychoanalyst
* John Lyth (1821–1886), English Wesleyan Methodist preacher, author, historian and hymn writer
* Mary Ann Lyth (1811-1890), English missionary, translator, and teacher
;In other
* Crosthwaite and Lyth, civil parish in the South Lakeland district of Cumbria, England
* Lyth Hill Countryside Site, Shropshire
* Lyth Valley, on the edge of the Lake District National Park in Cumbria, England
{{dab, surname, geo
