| Name | Type | Language | Counties |
|---|---|---|---|
| ELIZABETH ANN OLSON | Standardized | ||
| EUNICE BEVERLY OLSON | Standardized | English | Jackson, Josephine |
| Laura Ann Olson | Master | English | Clackamas, Marion, Multnomah, Polk, Yamhill |
| LINDA OLSON | Standardized | English | Umatilla |
| Kim (Kiki) Omoto | Master | English | Benton |
| CHRISTINA SUZANNE ONEILL | Master | English | All |
| LISSET ONEILL | Master | English, Spanish | Multnomah |
| Nancy L Orem | Master | English | All |
| RAUL DAVID OROZCO FUENTES | Master | English, Spanish | Benton, Linn, Marion, Polk |
| ANA LAURA ORTEGA | Standardized | Hood River, Wasco | |
| Kay Guadalupe Ortega | Standardized | English, Spanish | Jackson, Jefferson, Josephine, Klamath |
| MIRIAM NANCY ORTIZ VARGAS | Standardized | Crook, Deschutes, Jefferson | |
| ELENA ESMERALDA ORTIZ-ROBLES | Community | Spanish | Hood River, Multnomah, Wasco |
| WYNNE LOUISE OSBORNE | Community | English | Clackamas, Clatsop, Crook, Deschutes, Jefferson, Tillamook, Washington |
| CINDY RAE OVERSTREET | Master | English | Clackamas, Clatsop, Columbia, Multnomah, Washington |
| Angela Mary Oviedo | Standardized | English | Malheur |
| RUTH OXMAN | English | ||
| SARA PACKER | Not given | English | Multnomah |
| SHELLY Annette PADDOCK | Community | English | Clackamas, Marion, Multnomah, Polk, Washington, Yamhill |
| KARISSA LYNN PALMER | Master | English | All |