| Country: | South Korea |
| Season: | 2005 |
| Division1: | K League |
| Champions1: | Ulsan Hyundai Horang-i |
| Division2: | K2 League |
| Champions2: | Incheon Korail |
| Domestic: | Korean FA Cup |
| Dchampions: | Jeonbuk Hyundai Motors |
| Leaguecup: | Korean League Cup |
| Lchampions: | Suwon Samsung Bluewings |
| Supercup: | Korean Super Cup |
| Schampions: | Suwon Samsung Bluewings |
| Prevseason: | 2004 |
| Nextseason: | 2006 |
| Flagicon: | yes |
This article shows the summary of 2005 football season in South Korea. Ulsan Hyundai Horang-i and Jeonbuk Hyundai Motors became champions of the 2005 K League and 2005 Korean FA Cup respectively, and Busan IPark reached the semi-finals of the 2005 AFC Champions League. The South Korean national team qualified for the 2006 FIFA World Cup.
See main article: article and South Korea national football team results (2000–2009).
See also: 2006 FIFA World Cup qualification – AFC third round.
See also: 2005 East Asian Football Championship.
See main article: 2005 K League.
See main article: 2005 K League Championship.
See main article: 2005 K2 League.
See main article: 2005 Korean FA Cup.
See main article: 2005 Korean League Cup.
See main article: Korean Super Cup.
See main article: South Korean football clubs in the AFC Champions League.
| Team | Result | Round | Aggregate | Score | Venue | Opponent |
|---|---|---|---|---|---|---|
| Busan IPark | Semi-finals | Group G | Winners | 8–0 | Home | Bình Định |
| 4–0 | Away | |||||
| 2–0 | Away |  Krung Thai Bank | ||||
| 4–0 | Home | |||||
| 4–0 | Home |  Persebaya Surabaya | ||||
| 3–0 | Away | |||||
| Quarter-finals | 5–1 | 3–0 | Home |  Al-Sadd | ||
| 2–1 | Away | |||||
| Semi-finals | 0–7 | 0–5 | Home | Al-Ittihad | ||
| 0–2 | Away | |||||
| Suwon Samsung Bluewings | Group stage | Group E | Runners-up | 5–1 | Away | Hoang Anh Gia Lai |
| 6–0 | Home | |||||
| 0–0 | Home |  Shenzhen Jianlibao | ||||
| 0–1 | Away | |||||
| 2–1 | Home |  Júbilo Iwata | ||||
| 1–0 | Away |