World Sea Ports
| Port Name | Port Code | Country Name |
|---|---|---|
| Ochakiv | UAOCH | Ukraine |
| Ochiyo | JPOOC | Japan |
| Ocho Rios | JMOCJ | Jamaica |
| Öckerö | SEOCO | Sweden |
| Ocoa Bay | DOOCO | Dominican Republic |
| Ocoee | USOC7 | United States of America (the) |
| Odaejin | KPODA | Korea, Democratic People's Republic of |
| Odahigashi | JPODA | Japan |
| Odda | NOODD | Norway |
| Oddsta, Fetlar | GBODD | United Kingdom |