| Blazh | | - | Medieval Slavic | |
| Bogdan | | BAWG-dahn (Polish), BOG-dahn (Serbian, Croatian), bog-DAHN (Romanian) | Polish, Russian, Slovene, Bulgarian, Serbian, Croatian, Macedonian, Romanian, Medieval Slavic | |
| Bogdana | | bawg-DAH-nah (Polish) | Polish, Russian, Slovene, Bulgarian, Serbian, Macedonian, Romanian, Medieval Slavic | |
| Bogumil | | - | Medieval Slavic | |
| Bogumir | | - | Medieval Slavic | |
| Boguslav | | - | Medieval Slavic | |
| Boleslav | | - | Czech, Russian, Medieval Slavic | |
| Borislav | | bah-ree-SLAHF (Russian) | Bulgarian, Serbian, Croatian, Slovene, Russian, Medieval Slavic | |
| Borisu | | - | Medieval Slavic | |
| Borivoi | | - | Medieval Slavic | |
| Bozhena | | - | Medieval Slavic | |
| Bozhidar | | - | Bulgarian, Macedonian, Medieval Slavic | |
| Bozho | | - | Medieval Slavic | |
| Bratomil | | - | Medieval Slavic | |
| Bratoslav | | - | Medieval Slavic | |