Ernest Castle Sykes (31 May 1869 – 30 November 1925) was an English first-class cricketer. Sykes was a right-handed batsman who played primarily as a wicketkeeper. Sykes represented Hampshire in one first-class match in 1896 against the touring Australians. Dean was 0* at the close of Hampshire's first innings and their second innings scored Sykes scored 5*, leaving him with no batting average due to his not out scores. Sykes died in Bolsover, Derbyshire on 30 November 1925. His son Eric played for Derbyshire.