Martyn Davies who made a record number of appearances for the Welsh All Blacks over 15 years from 1963.
The club led tributes to the former head teacher described by officials as a great ambassador both for the sport and his home town.
A funeral service for Mr Davies, who died while on a walking holiday in the French Alps, will be held on Saturday.
The scrum-half played for the club 511 times before he retired - a record that has never beaten.
He captained the side for four years, including the 1971/72 centenary season.
After his playing days were over he became Neath and Welsh youth team coach and served on the club's management board.
Outside rugby he was a former head teacher at Blaenhonddan Junior School in Bryncoch and was then involved in education administration.
A spokesman for the club said: "It's a tragic loss to his family and the whole of the Neath area.
"He was a great rugby player and a credit to the town.
"Neath rugby club will not be the same without Martyn who will be sorely missed by all who knew him."