| Regimental number | 1565 |
| Religion | Roman Catholic |
| Occupation | Labourer |
| Address | Moss Vale, New South Wales |
| Marital status | Single |
| Age at embarkation | 27 |
| Next of kin | Father, Terence Arthur O'Brien, Foxton, New Zealand |
| Enlistment date | 13 September 1915 |
| Date of enlistment from Nominal Roll | 20 September 1915 |
| Rank on enlistment | Private |
| Unit name | 7th Light Horse Regiment, 12th Reinforcement |
| AWM Embarkation Roll number | 10/12/3 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board SS Hawkes Bay on 23 October 1915 |
| Rank from Nominal Roll | Driver |
| Unit from Nominal Roll | 10th Field Artillery Brigade |
| Fate | Returned to Australia 1 May 1919 |
| Miscellaneous details (Nominal Roll) | *Spelt Terence O'Farell O'Brien on NR |
