Roy Mathias (born 2 September 1949) is a Welsh dual-code international rugby union and professional rugby league, and footballer who played in the 1960s, 1970s and 1980s. He played representative level rugby union (RU) for Wales, and at club level for Felinfoel RFC and Llanelli RFC, as a wing, i.e. number 11 or 14, and representative level rugby league (RL) for Great Britain and Wales, and at club level for St. Helens and Cardiff City (Bridgend) Blue Dragons, as a wing, or loose forward, i.e. number 2 or 5, or 13, during the era of contested scrums.