Barnes, who takes up his new role on Monday, was head of showbusiness, media and arts at the Press Association for nearly six years.
Barnes was also the arts and media correspondent for the Independent on Sunday and has held roles with Q magazine, Classic FM and Record Collector.
UK Music is an umbrella group representing the collective interests of the country's music industry, working closely with industry and government.
Barnes replaces James Murtagh-Hopkins, who left UK music in September to join music industry giant Universal Music Group
as its senior director of comms.
He will report to UK Music’s chief executive Jo Dipple, who said: "There is a copyright package going through Europe. Brexit is looming. The Digital Economy Bill is being scrutinised by Parliament. The collective voice of the music industry needs a steady hand and Anthony is the right person at the right time."
Barnes said: "I feel excited and privileged to be joining the team. I'm looking forward to building on UK Music’s considerable achievements in representing the successes of the industry and putting the case for change and support where it is needed."