First Battalion Four Marines
Personnel Rosters - Delta Company
1 January - 31 December 1969
Tour Date - When Joined Company
| Name | Rank | MOS | Tour | Purple Heart | Purple Heart | KIA |
| O'Bryan, Mark J | L/Cpl | 0311 | 7 May 69 | |||
| O'Connell, D J | L/Cpl | 0351 | 17 Apr 69 | |||
| Orlandella, R A | 2nd Lt | 0302 | ||||
| Orr, H L | Sgt | 0311 | ||||
| Orta, Fernando | PFC | 0311 | 17 Aug 69 | |||
| Ortega, F W | PFC | 0311 | 27 Jul 69 | |||
| Ostertag, Donald J | Cpl | 0351 | ||||
| Outten, Thomas L | PFC | 0341 | ||||
| Ozell, M | PVT | 0351 | 3 Dec 69 | |||