Human platelet alloantigens (HPA) are specific antigens carried by platelet glycoproteins, which genes showing single nucleotide polymorphism. HPA can induce alloantibodies bringing about alloimmune response. They play important roles in post-transfusion refractoriness to platelets, post-transfusion thrombocytopenic purpura, fetomaternal alloimmune thrombocytopenia, and graft-versus-host disease. Because of their side effects in clinical blood-transfusion, there were a great deal of studies on HPA during last few decades. This review focuses on the nomenclature of HPA, the polymorphisms of platelet glycoproteins, HPA typing of the serological and molecular technology, as well as the mechanism of alloimmunization to HPA and correlated diseases.