| Competition: | Daum Challengers League |
| Season: | 2012 |
| Dates: | 3 March – 24 November 2012 |
| Winners: | FC Pocheon (2nd title) |
| Best Player: | Kang Seok-gu[1] |
| League Topscorer: | Seo Dong-hyeon (31 goals) |
| Best Goalkeeper: | Kang Jae-wook |
| Matches: | 228 |
| Total Goals: | 996 |
| Prevseason: | 2011 |
| Nextseason: | 2013 |
The 2012 Challengers League was the sixth season of amateur K3 League.
The Challengers League maintained home and away season of two groups and a one-time interleague play. The winners and runners-up of both groups qualified for the championship playoffs like before. On the basis of the overall standings, however, third and fourth-placed club entered the first round, and second and first-placed club directly advanced to the semi-final and final respectively.
18 clubs participated in this season after Jungnang Chorus Mustang and Paju Citizen joined the league. Asan Citizen moved its city to Yesan before the start of the season, and changed its name to Yesan Citizen.
| Club | City | Stadium | Manager | |
|---|---|---|---|---|
| Bucheon FC 1995 | Bucheon | Bucheon Stadium |  Gwak Kyung-keun | |
| Cheonan FC | Cheonan | Cheonan Football Center | Park Yoon-ki | |
| Cheongju Jikji | Cheongju | Cheongju Stadium | Kim Jong-hyun | |
| Chuncheon FC | Chuncheon | Chuncheon Stadium | Ham Cheol-kwon | |
| Goyang Citizen | Goyang | Goyang Eoulimnuri ground | Kim Jin-ok | |
| Gwangju Gwangsan | Gwangju | Honam University ground | Hwang Young-woo | |
| Gyeongju Citizen | Gyeongju | Gyeongju Civic Stadium | Kim Jin-hyung | |
| Icheon Citizen | Icheon | Icheon City Stadium | Lee Hyun-chang | |
| Jeonju EM | Jeonju | Jeonju University ground | Oh In-eui | |
| Jungnang Chorus Mustang | Seoul | Jungnang Public Ground | Kim Sang-hwa | |
| Namyangju United | Namyangju | Namyangju Stadium | Lee Jong-woon | |
| Paju Citizen | Paju | Paju Stadium | Cho Deok-jeung | |
| FC Pocheon | Pocheon | Pocheon Stadium | Lee Su-sik | |
| Seoul FC Martyrs | Seoul | Gangbuk Stadium | Yoo Bong-ki | |
| Seoul United | Seoul | Madeul Stadium | Bae Hyung-ryul | |
| Yangju Citizen | Yangju | Yangju Stadium | Kim Jong-boo | |
| Yeonggwang FC | Yeonggwang | Yeonggwang Sportium | Kim Han-bong | |
| Yesan Citizen | Yesan | Yesan Stadium | Choi Jong-duk |