Ysgol y Creuddyn (Welsh pronunciation: [ˈəskɔl ə ˈkrɛɨðɨn]) is a Welsh-medium secondary school, situated in Penrhyn Bay outside Llandudno, Wales, named after the Creuddyn peninsula. The school was founded on Wednesday, the 2nd of September 1981 with 218 students. As of 2023, 633 pupils are enrolled at the school.

Students are bilingual, with all subjects taught in the Welsh language (apart from English and French lessons) up to GCSE level. In 2024, 59.9 per cent of the pupils spoke Welsh at home.

The school is the predominant Welsh language school in the area, and it serves pupils from a wide area including Abergele, Colwyn Bay, Betws yn Rhos, Conwy, Llandudno, Llanfairfechan, Penmaenmawr and Eglwysbach. The school teaches children from the ages of 11 to 18, and is well known for students attaining successful grades at GCSE and A-level.

Notable former pupils

• Russell Jones, actor
• Al Lewis, singer-songwriter
• David Vaughan, Footballer