| Religion | Roman Catholic |
| Occupation | Clerk |
| Address | Melbourne, Victoria |
| Marital status | Single |
| Age at embarkation | 20 |
| Next of kin | Father, Michael George O'Brien, 17 Grandview Grove, Aramdale, Victoria |
| Enlistment date | 19 August 1914 |
| Rank on enlistment | 2nd Lieutenant |
| Unit name | 59th Battalion, 9th Reinforcement |
| AWM Embarkation Roll number | 23/76/4 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A16 Port Melbourne on 16 July 1917 |
| Rank from Nominal Roll | Lieutenant |
| Unit from Nominal Roll | 59th Battalion |
| Fate | Returned to Australia 1 August 1918 |
