| Regimental number | 3534 |
| Place of birth | Goondiwindi, Queensland |
| Religion | Roman Catholic |
| Occupation | Farmer |
| Address | Goondiwindi, Queensland |
| Marital status | Single |
| Age at embarkation | 21.6 |
| Height | 5' 6" |
| Weight | 121 lbs |
| Next of kin | Father, Michael James O'Leary, Goondiwindi, Queensland |
| Previous military service | Nil |
| Enlistment date | |
| Place of enlistment | Warwick, Queensland |
| Rank on enlistment | Private |
| Unit name | 47th Battalion, 9th Reinforcement |
| AWM Embarkation Roll number | 23/64/3 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A33 Ayrshire on |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 47th Battalion |
| Fate | Returned to Australia |
| Discharge date | |
| Other details |
War service: Western Front Missing in action, Belgium, 12 October 1918; subsequently reported Prisoner of War, Germany. Repatriated, arrived United Kingdom, 30 December 1918. Commenced return to Australia on board HT 'Plassy', 7 March 1919; discharged (termination of period of enlistment), Brisbane, 7 June 1919. Medals: British War Medal, Victory Medal |
| Sources | NAA: B2455, O'LEARY John Michael |