The 16-cap Wales number eight died in his sleep on a charity trek on the Inca Trail in Peru.
The popular BBC commentator rose to prominence with Pontypool in the 1970s, representing Wales between 1980 and 1984.
Butler toured New Zealand with the British and Irish Lions in 1983, before forging a highly respected career as a commentator and broadcaster.
Charity Prostate Cymru, for whom Butler served as an ambassador, also shared the news.
"The Prostate Cymru charity is devastated by the passing of its much loved ambassador Eddie Butler," read a statement.
"Eddie was the voice of Wales and we were honoured to have him as part of our charity. We will cherish the many memories we have of him.
"Over the last week Eddie once again showed his generosity and steadfast commitment to good causes by joining 25 Prostate Cymru fundraisers, including his daughter Nell, on the Inca Trail Trek to Machu Picchu.
"In the early hours of Thursday, September 15, Ed passed away peacefully in his sleep at Ecoinka base camp in the Peruvian Andes.
"He leaves behind his wife Susan and six children, who are very much in our thoughts."