2012 Regional League Division 2 Northern Region is the fourth season of the league competition since its establishment in 2009. It is in the third tier of the Thai football league system.
No club was promoted to the Thai Division 1 League. Last year's league champions, Phitsanulok, and runners up, Lamphun Warrior, failed to qualify from the 2011 Regional League Division 2 championship pool.
Chiangmai were relegated from the 2011 Thai Division 1 League.
Paknampho NSRU relocated to the Regional League Northern Division from the Regional League Bangkok Area Division.
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