Sain (Welsh for Sound), in full - Recordiau Sain Cyf (Sound Records Ltd) is a Welsh record label, which played an important role in the Welsh folk revival.
Also credited as .

It was founded in Cardiff in 1969 by singer/songwriters Dafydd Iwan and Huw Jones, and businessman Brian Morgan Edwards, as a home for Welsh-language rock and folk music, which was otherwise finding it difficult to 'break through' in the UK market. The company released its first single in October 1969, Huw Jones’ Dŵr (Welsh for Water), a song about the drowning of the Tryweryn Valley, in the north-west of Wales, to form Llyn Celyn reservoir. Many of the company’s early releases were recorded at the Rockfield Studios in Monmouthshire. In the early 1970s Sain moved to the Caernarfon area, and opened their first recording studio in 1975 near Llandwrog. Today Sain remains the biggest producer of music of Wales, covering traditional, folk, rock, pop, hip-hop, rap, country and classical music. Rasal Cyf. is the latest label, and this signs young Welsh bands.