A prolonged APTT does not confirm a diagnosis of hemophilia, it is only an abnormal indicator in the hemophilia test, and generally patients with hemophilia will have a prolonged APTT beyond the normal range. The APTT is a more sensitive indicator of endogenous coagulation system detection, with a normal value of 35-45 seconds, generally more than 10 seconds to have pathological significance, common APTT prolongation is mostly seen in hemophilia, but not necessarily with It is also seen in diffuse intravascular bleeding, fibrinogenopenia, etc. A series of tests such as vWf and endogenous factor testing are needed to confirm the diagnosis. Hemophilia is a familially inherited blood disorder with common symptoms of easy bleeding after minor trauma, difficult to cure and lifelong alternative treatment.