2009 Regional League Division 2 was contested by the five regional league winners of the 3rd level championships of Thailand.
Five teams met on a home and away basis, with the top three teams gaining promotion to the Thai 1st Division for the 2010 campaign.
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<span style="color:red;">Red Zone</span>:2009 Regional League Division 2 Bangkok Metropolitan Region<br /> <span style="color:#ffff00;">Yellow Zone</span>:2009 Regional League Division 2 Central & Eastern Region<br /> <span style="color:#008000;">Green Zone</span>: 2009 Regional League Division 2 Northern Region Region<br /> <span style="color:Orange;"> Orange Zone</span>:2009 Regional League Division 2 North Eastern Region<br /> <span style="color:blue;">Blue Zone</span>:2009 Regional League Division 2 Southern Region<br>
The 2009 Regional League Division 2 winners were Raj Pracha-Nonthaburi FC