2009–10 Northern Football League

The 2009–10 Northern Football League season was the 112nd in the history of Northern Football League, a football competition in England.

Division One
Division One featured 19 clubs which competed in the division last season, along with three new clubs, promoted from Division Two:
 * Esh Winning
 * Horden Colliery Welfare
 * Norton & Stockton Ancients

Also, Dunston Federation changed name to Dunston UTS.

Division Two
Division Two featured 16 clubs which competed in the division last season, along with four new clubs:
 * Gillford Park, promoted from the Northern Football Alliance
 * Newton Aycliffe, promoted from the Wearside Football League
 * Northallerton Town, relegated from Division One
 * Seaham Red Star, relegated from Division One

Also, Stokesley Sports Club changed name to Stokesley.