| Regimental number | 2477 |
| Place of birth | Gerringong New South Wales |
| Religion | Roman Catholic |
| Occupation | Butcher |
| Address | Corrimal Street, Wollongong, New South Wales |
| Marital status | Single |
| Age at embarkation | 20 |
| Next of kin | Father, Harry O'Brien, Corrimal Street, Wollongong, New South Wales |
| Enlistment date | 2 November 1915 |
| Rank on enlistment | Private |
| Unit name | 5th Light Horse Regiment, 17th Reinforcement |
| AWM Embarkation Roll number | 10/10/4 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A10 Karroo on 5 May 1916 |
| Rank from Nominal Roll | Driver |
| Unit from Nominal Roll | Australian Mounted Divisional Train |
| Fate | Returned to Australia 24 July 1919 |