Llywarch

Llywarch may refer to:


 * Llywarch Hen (6th century), Brythonic prince and poet
 * Llywarch ap Hyfaidd (died c. 904), king of Dyfed
 * Llywarch ap Llywelyn (fl. 1173–1220), medieval Welsh poet.
 * Llywarch Llaety (fl. 1140–1160), Welsh court poet
 * Llywarch Reynolds (1843–1916), Welsh solicitor and scholar