1998–99 Sussex County Football League

The 1998–99 Sussex County Football League season was the 74th in the history of Sussex County Football League a football competition in England.

Division One
Division One featured 17 clubs which competed in the division last season, along with three new clubs, promoted from Division Two:
 * Broadbridge Heath
 * East Preston
 * Eastbourne United

Division Two
Division Two featured 13 clubs which competed in the division last season, along with five new clubs.
 * Clubs relegated from Division One:
 * Arundel
 * Mile Oak
 * Peacehaven & Telscombe
 * Clubs promoted from Division Three:
 * Lingfield
 * Storrington

Division Three
Division Three featured 13 clubs which competed in the division last season, along with three new clubs:
 * Bexhill Town, relegated from Division Two
 * Midhurst & Easebourne, relegated from Division Two
 * Wealden