B50 or B-50 may refer to: B-50 Superfortress, an airplane BSA B50, 500cc motorcycle International Statistical Classification of Diseases and Related Health Problems (ICD-10), code for Plasmodium falciparum malaria Leyland Royal Tiger, a UK bus Sicilian Defence, an Encyclopaedia of Chess Openings code A Vietnamese RPG-2 rocket-propelled grenade launcher B-50, alias of Gap-43 protein HLA-B50, a HLA-B serotype