This is the progression of world record improvements of the 400 metres hurdles M45 division of Masters athletics.
- Key
Incomplete information Pending
| Hand | Auto | Athlete | Nationality | Birthdate | Location | Date |
|---|---|---|---|---|---|---|
| 53.57 | Aramis Diaz |  Italy
|
22 November 1974 | Rome | 5 September 2020 | |
| 53.90 | Aramis Diaz | Italy
|
22 November 1974 | Padova | 29 August 2020 | |
| 54.92 | Edward Betts |  United Kingdom
|
18 February 1971 | Palencia | 9 July 2016 | |
| 55.18 | Guido Müller |  Germany
|
22 December 1938 | Malmö | 1 August 1986 | |
| 55.7 | Jack Greenwood |  United States
|
5 February 1926 | San Diego | 24 August 1972 |