Ystradfellte is a village and community located in Powys, Wales. Situated approximately 6 miles (10 km) north of Hirwaun, it has a population of 556 inhabitants. The village belongs to the historic county of Brecknockshire (Breconshire).
The community is situated within the Fforest Fawr area of the Brecon Beacons National Park and lies beside the Afon Mellte river. It is connected by minor roads to Heol Senni to the north, the A4059 north of Penderyn, and Pontneddfechan to the south at the head of the Vale of Neath. For postal purposes, Ystradfellte falls under Aberdare.