The BBC National Orchestra of Wales (BBC NOW) (Welsh: Cerddorfa Genedlaethol Gymreig y BBC) is a Welsh symphony orchestra and one of the BBC's five professional radio orchestras. The BBC NOW is the only professional symphony orchestra organisation in Wales, occupying a dual role as both a broadcasting orchestra and national orchestra. The BBC NOW has its administrative base in Cardiff, at the BBC Hoddinott Hall on the site of the Wales Millennium Centre, since January 2009.

The BBC NOW is the orchestra-in-residence at St David's Hall, Cardiff, and also performs regularly throughout Wales and beyond, including international tours and annual appearances at the Royal Albert Hall in London at the BBC Proms. Broadcasting work includes studio sessions for BBC Radio and television, although the orchestra's concerts form the bulk of its broadcasts, transmitted primarily on BBC Radio 3 but also on BBC Radio Wales, BBC Radio Cymru and BBC Television. The orchestra records many soundtracks for BBC television, including Doctor Who, Torchwood, Human Planet, and Earthflight.