Llanuwchllyn is a village and community in Gwynedd, Wales, near the southern end of Bala Lake. It is one of the most sparsely populated communities in Wales. The electoral ward includes the small settlement of Llangywer. The parish church of St Deiniol is a Grade II* listed building. Llanuwchllyn railway station is the headquarters of the narrow gauge Bala Lake Railway, centred on the former Great Western Railway station on the standard-gauge line from Ruabon to Barmouth.