Llywelyn ap Gruffydd

Llywelyn ap Gruffydd may refer to:


 * Llywelyn ap Gruffydd (c. 1223 – 1282), more commonly known as Llywelyn ap Gruffudd, also known as Llywelyn Ein Llyw Olaf (Llywelyn, Our Last Leader), Llywelyn the Last, Prince of Wales 1258–1282
 * Llywelyn ap Gruffydd Fychan (c. 1341 – 1401), wealthy Carmarthenshire landowner executed by Henry IV of England in punishment for his support of Owain Glyndwr's Welsh rebellion