John Fearn (fl. 1798) was an English whaling ship captain, notable as the first European to discover the Pacific island of Nauru, which is now a sovereign republic. He was probably born on 24 August 1768 in Kingston upon Hull Note: He has frequently been confused with John Fearn (philosopher) (1768-1837), a British philosopher who had spent some years as an officer in the Royal Navy.
John Fearn discovered Nauru on 8 November 1798, while travelling with his whaling ship Hunter from New Zealand to China. He named it Pleasant Island due to its attractive environment and the friendly nature of the Nauruans.
Fearn was commemorated on the obverse of a $10 Nauruan coin.