| Name | Section | Lot | Grave No. | Date of Death | Age | Veteran(rank, branch) | Veteran Of | WWFD |
| Oakley, Lawrence J. | New Ground | 35 | 4 | 1/7/2012 | 65 | | | |
| O'Brien, Elizabeth M. | 2nd Section | 512 | 4 | 11/16/2014 | 102 | | | |
| O'Brien, Katherine Irene 'Kim' (Mehrtens) | New Ground | 202 | 1 | 8/9/2016 | 66 | | | |
| O'Brien, William Smith | 2nd Section | 512 | 3 | 1/18/1992 | 79 | Veteran | | |
| Ockenden, Elizabeth Irene (Hammer) | New Ground | 65 | 5 | 5/13/2011 | 82 | | | |
| Ockenden, Frank E. III | New Ground | 65 | 4 | 12/26/1979 | 52 | S1, US Navy | WWII | |
| O'Connor, Aida E. | 2nd Section | 116 | 5 | 7/4/1954 | 69 | | | |
| Ogden, Doris May (Hall) | New Ground | 70 | 2 | 3/7/2017 | 76 | | | |
| O'Hare, Nicolette | Second | 451 | 4 | 07/16/2022 | 90 | | | |
| O'Hare, Richard F. | 2nd Section | 451 | 3 | 12/26/2010 | 76 | | | WWFD |
| O'Hare, Timothy Michael | 2nd Section | 241 | 5 | 2/17/1969 | 1 day | | | |
| Olmstead, Helen (Littlefield) | Old East | 41 | 4 | 10/15/1975 | 72 | | | |
| Olmstead, Leslie | Old East | 41 | 5 | 2/25/1976 | 80 | | | |
| O'Neil, Hortnese E. (Deutschbein) | 2nd Section | 392 | 3 | 2/26/1927 | 27 | | | |
| Orr, Harley Eugene | 2nd Section | 524 | 1 | 4/13/2001 | 65 | | | |
| Orr, Ina Elvey | Second | 524 | 1 | 01/02/2021 | 84 | | | |
| Orr, Joshua R. | 2nd Section | 522 | 2 | 01/01/2024 | 29 | | | |
| Orr, Kimberly J. (Consersi) | New Ground | 92 | 2 | 6/28/1992 | 29 | | | |
| Ouimet, Donald M. | 2nd Section | 433 | 4 | 9/18/1961 | 7 mos. | | | |
| Outwater, Alford E. | Old West | 71 | 1 | 1/15/1945 | 82 | | | |
| Outwater, Alma F. | Old West | 71 | 2 | 8/7/1924 | 62 | | | |
| Owens, Marguerite A. (Shaw) | New Ground | 143 | 4 | 3/20/2003 | 84 | | | |
| Owens, Robert E. | New Ground | 143 | 3 | 2/3/2005 | 78 | CPL, US Army Air Forces | | |
| Oyphanith, Tem | New Ground | 111 | 1 | 7/28/1993 | 64 | | | |
| Oyphanith, Thongsy K. | New Ground | 111 | 2 | 6/14/1991 | 61 | | | |