Athletics at the 1912 Summer Olympics – Men's marathon
The men's marathon was a track and field athletics event held as part of the athletics at the 1912 Summer Olympics programme. It was the fifth appearance of the event, which is one of 12 athletics events to have been held at every Summer Olympics. The distance used was 40.2 kilometres, nearly 2 full kilometres shorter than that used in 1908 and since 1924. The competition was held on Sunday, July 14, 1912.
Sixty-eight runners from 19 nations competed. NOCs could enter up to 12 athletes.
With conditions described as "very hot", only half of the competitors finished.
Records
These were the standing world and Olympic records prior to the 1912 Summer Olympics.| World Record | 2:40:35 |  Thure Johansson | Stockholm | August 31, 1909 |
| Olympic Record | 2:55:18.4 |  Johnny Hayes | London | July 24, 1908 |
The distance was nearly two kilometres shorter; nevertheless, Ken McArthur's winning time is registered as an Olympic record.
Results
| Place | Athlete | Time | Notes |
| 1 | 2:36:54.8 | OR | |
| 2 | 2:37:52.0 | ||
| 3 | 2:38:42.4 | ||
| 4 | 2:42:07.9 | ||
| 5 | 2:42:18.8 | ||
| 6 | 2:43:24.9 | ||
| 7 | 2:44:19.4 | ||
| 8 | 2:45:47.2 | ||
| 9 | 2:46:40.7 | ||
| 10 | 2:49:49.4 | ||
| 11 | 2:50:36.2 | ||
| 12 | 2:50:46.6 | ||
| 13 | 2:51:06.6 | ||
| 14 | 2:52:11.4 | ||
| 15 | 2:52:23.0 | ||
| 16 | 2:52:41.4 | ||
| 17 | 2:52:53.8 | ||
| 18 | 2:59:35.4 | ||
| 19 | 3:00:05.0 | ||
| 20 | 3:00:48.0 | ||
| 21 | 3:01:39.2 | ||
| 22 | 3:02:05.2 | ||
| 23 | 3:04:59.4 | ||
| 24 | 3:06:13.0 | ||
| 25 | 3:09:25.0 | ||
| 26 | 3:11:37.0 | ||
| 27 | 3:13:32.2 | ||
| 28 | 3:16:35.2 | ||
| 29 | 3:21:57.4 | ||
| 30 | 3:21:57.6 | ||
| 31 | 3:25:21.6 | ||
| 32 | 3:26:56.4 | ||
| 33 | 3:27:03.8 | ||
| 34 | 3:36:35.2 | ||
| 35 | Unknown | ||
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