| OAKLEY | Frank | L/Cpl | 3422 | Kingsbury | | | | Machine Gun Corp |
ODAM
| Alfred | | | Shuttingham & Alvecote Memorial | | | | |
| OLIVER | William | | | Ansley | | | | |
| OLIVER-BELLASIS | R | | | Shilton Roll of Honour | | | | |
| ONLY | William | | | Nuneaton Abbey Church St Mary's | | | | |
| ORAM | Frank | Pte | 12080 | Nuneaton Riversley Park | | | | Royal Warwickshire |
| ORME | John | Pte | 20731 | Glascote | | | | Royal Warwickshire |
| ORTON | William Henry | Rfn | Y/1002 | Atherstone Sheepy Road Cemetery | | | | King's Royal Rifle Corps |
| ORTON | Lewis | Pte | 62237 | Nuneaton Riversley Park | | | | Canterbury Regiment (NZ Expeditionary Force) |
| ORTON | Arthur John | Pte | 203119 | Nuneaton Riversley Park | | | | Royal Warwickshire |
| ORTON | James | Pte | 7602 | Nuneaton Riversley Park Addendum | | | | Coldstream Guards |
| ORTON | William | Pte | 18674 | Warton | | | | Leicestershire Regiment |
| ORTON | Charles | A/Cpl | 10757 | Wilnecote Holy Trinity | | | | Royal Warwickshire |
| OSBORNE | Edward Bertram | 2ndLt | | Atherstone Grammar School | | | | East Lancashire Regiment |
| OVERTON | Ernest Alexander | Pte | 11604 | Nuneaton Riversley Park | | | | Royal Warwickshire |
| OWEN | John[T] | Pte | 13076 | Nuneaton Riversley Park | | | | Royal Warwickshire |
| OWEN | Arthur Herbert | Cpl | 10555 | Orton-on-the-Hill | Polesworth Pooley Hall Colliery | | | Royal Warwickshire |
| OWEN | William H | Pte | 235305 | Wilnecote Holy Trinity | | | | Lancashire Fusilers |
| OXFORD | William(Arthur) | Cpl | 16045 | Ansley | Merevale | | | Royal Warwickshire |
| OZIERBROOK | John Henry | L/Cpl | 831 | Nuneaton Riversley Park | | | | Royal Warwickshire |