Blood type B positive means that a person’s blood type is B in the ABO blood type system and RH positive in the RH blood type system, which is the most comprehensive description of a person’s blood type. The RH blood group system is divided into two types according to whether the patient’s red blood cell membrane contains D antigen or not, those containing D antigen are RH positive and those not containing D antigen are RH negative. Blood type B positive means that the ABO blood type is B blood and the RH blood type is RH positive blood.