| Omid Malik Khel | Belgium | - | - | T10 |
| Omid Osmanzai | Germany | - | - | - |
| Omid Rahimi | Belgium | right-hand-bat | right-arm-fast | T10 |
| Omid Rahman | United Arab Emirates | - | - | ODI, T10, T20I |
| Omid Rehma | United Arab Emirates | - | - | Youth ODI |
| Omid Rehman | United Arab Emirates | right-hand-bat | right-arm-fast-medium | T20I |
| Omkar Kadkol | India | right-hand-bat | right-arm-offbreak | - |
| Omkar Kunte | Germany | right-hand-bat | - | T10 |
| Omkar Patil | Germany | - | - | T10 |
| Omkar Shiriskar | Germany | - | - | T10 |
| Ommi Bhaswanth Krishna | India | - | - | - |
| Omosigho Eguakun | Nigeria | right-hand-bat | - | T20I |
| Omphile Ramela | South Africa | left-hand-bat | slow-left-arm-orthodox | - |
| Omran Zazai | Sweden | right-hand-bat | right-arm-fast | T10 |
| Onais Bascome | Bermuda | right-hand-bat | right-arm-fast-medium | T20I |
| Onaje Amory | West Indies | right-hand-bat | right-arm-offbreak | Youth ODI |
| Onka Ozkul | Turkey | - | - | T10 |
| Onkar Gurav | India | right-hand-bat | - | - |
| Onkar Jadhav | India | right-hand-bat | - | T20 |
| Onkar Singh | India | right-hand-bat | right-arm-fast-medium | T10 |
| Onkar Singh | Italy | - | - | T10 |
| Onkar Singh | Portugal | right-hand-bat | right-arm-fast | T10 |
| Onkar Tarmale | India | right-hand-bat | right-arm-fast-medium | T20 |
| Onkar Tavate | India | right-hand-bat | right-arm-fast | - |
| Onke Nyaku | South Africa | right-hand-bat | right-arm-fast-medium | List A, ODI, T20 |
| Onnicha Kamchomphu | Thailand | right-hand-bat | right-arm-offbreak | ODI, T20I |
| Onur Ozkul | Turkey | right-hand-bat | right-arm-fast | T10 |
| Orapeleng Motlhoaring | South Africa | right-hand-bat | right-arm-fast-medium | T20, T20I |
| Orla Montgomery | Scotland | - | - | T20I |
| Orla Prendergast | Ireland Republic | right-hand-bat | right-arm-fast-medium | List A, ODI, T20, T20I |
| Ornob Masum | Bangladesh | right-hand-bat | right-arm-fast-medium | T10 |
| Oronde Bascome | Bermuda | right-hand-bat | right-arm-fast-medium | T20I |
| Osaid Haider | Hungary | - | - | - |
| Osama Hassan Shah | United Arab Emirates | right-hand-bat | legbreak-googly | , ODI, T10, T20, Youth ODI |
| Osama Mahmood | Switzerland | left-hand-bat | right-arm-fast | T10, T20, T20I |
| Osama Qureshi | Sweden | - | - | T10 |
| Osama Saleem | Sweden | - | - | T10 |
| Osama Shah | United Arab Emirates | right-hand-bat | legbreak-googly | T10, T20 |
| Osama Zafar | Pakistan | right-hand-bat | right-arm-fast | - |
| Oscar Duff | Bulgaria | right-hand-bat | right-arm-fast | T10 |
| Oscar Jackson | New Zealand | right-hand-bat | right-arm-fast-medium | 4day, List A, T20, Youth ODI |
| Oscar Mabin | New Zealand | right-hand-bat | right-arm-fast-medium | 4day |
| Oscar Mikhail | England | right-hand-bat | - | T10 |
| Oscar Partner | England | right-hand-bat | - | - |
| Oscar Whiteman | Luxembourg | right-hand-bat | right-arm-fast-medium | T10 |
| Oshada Fernando | Sri Lanka | right-hand-bat | legbreak | List A, ODI, T20, T20I, Test/5day |
| Oshada Jayawickrama | Sri Lanka | right-hand-bat | - | T10 |
| Oshadi Ranasinghe | Sri Lanka | left-hand-bat | right-arm-fast-medium | ODI, T20I |
| Oshane Thomas | West Indies | left-hand-bat | right-arm-fast | ODI, T10, T20, T20I |
| Osman Ibrahim | Finland | - | - | T20 |