| SL | Common Name | Local Name | Scientific Name | Domain | Kingdom | Phylum | Class | Order | Family | Genus | Species | Sub Species |
| 51 | Bengal Fox | Hiyal | Vulpes bengalensis | Eukaryota | Animalia | Chordata | Mammalia | Carnivora | Canidae | Vulpes | bengalensis | |
| 52 | Bengal Loach | Bagh Mach | Botia dario | Eukaryota | Animalia | Chordata | Actinopterygii | Cypriniformes | Cobitidae | Botia | dario | |
| 53 | Bengal Monitor | Mati Gui | Varanus bengalensis | Eukaryota | Animalia | Chordata | Reptilia | Squamata | Varanidae | Varanus | bengalensis | |
| 54 | Bengal Tiger | Bagh | Panthera tigris tigris | Eukaryota | Animalia | Chordata | Mammalia | Carnivora | Felidae | Panthera | tigris | tigris |
| 55 | Bengala Barb | Elang | Megarasbora elanga | Eukaryota | Animalia | Chordata | Pisces | Cypriniformes | Cyprinidae | Megarasbora | elanga | |
| 56 | Betel Leaf | Paan | Piper betle | Eukaryota | Plantae | Angiosperm | Dicots | Piperales | Piperaceae | Piper | betle | |
| 57 | Betel nut | Tamul | Areca catechu | Eukaryota | Plantae | Angiosperm | Monocots | Aracales | Aracaceae | Areca | catechu | |
| 58 | Bigeye Ilisha | Ilish | Ilisha megaloptera | Eukaryota | Animalia | Chordata | Pisces | Clupeiformes | Pristigasteridae | Ilisha | megaloptera | |
| 59 | Bighead Carp | Bighead | Hypophthalmichthys nobilis | Eukaryota | Animalia | Chordata | Actinopterygii | Cypriniformes | Cyprinidae | Hypophthalmichthys | nobilis | |
| 60 | Bitter Gourd | Tita kerela | Momordica charantia | Eukaryota | Plantae | Angiosperm | Dicots | Cucurbitales | Cucurbitaceae | Momordica | charantia |