B type Rh positive means that the person’s blood type system is B blood type in the ABO blood system and positive blood type in the Rh blood system. The ABO blood group system is named according to whether or not the red blood cell membrane contains the corresponding antigen, those containing the A antigen are A blood type, those containing the B antigen are B blood type. Rh positivity is determined by the presence or absence of the D antigen on the red blood cell membrane, with those containing the D antigen being Rh positive and those not containing the D antigen being Rh negative. Therefore, B type Rh positive means that the ABO blood type is B blood and the Rh blood type system is positive blood.