Randolph Turpin triumphed in the middleweight contest on 10 July 1951, with the 65th anniversary being marked at Gwyrch Castle, near Abergele.
It was there he trained for an unsuccessful rematch before he retired to run a pub in Llandudno.
Events including exhibition fights will celebrate the life of the English-born boxer on Saturday and Sunday.
Mr Turpin died in 1966, aged 37.
The life of a British world champion who beat the legendary boxer Sugar Ray Robinson will be celebrated in Conwy.