Cardiff Rugby (Welsh: Rygbi Caerdydd) is one of the four professional Welsh rugby union teams. They compete in the United Rugby Championship and in European Professional Club Rugby competitions.

Based in Cardiff, the team play at Cardiff Arms Park and are the professional arm of Cardiff Rugby Ltd. From 2003 to 2021 the first team was known as the Cardiff Blues before rebranding to Cardiff Rugby prior to the start of the 2021-22 season.

They won European Challenge Cup titles in 2010 and 2018, beating Toulon Rugby and Gloucester Rugby respectively. They most recently made the knockout stages of the European Rugby Champions Cup in 2012.

Between 2005 and 2018, they also competed in the Anglo-Welsh Cup and won the 2009 title, beating Gloucester at Twickenham.