Hemophilia A, caused by a deficiency or dysfunction of coagulation factor VIII, is challenging to manage clinically. To improve understanding and treatment, GemPharmatech developed the B6-F8-KO mouse model by knocking out exons 16 and 17 of the mouse F8 gene. This model, exhibiting significantly reduced F8 expression and resembling moderate hemophilia A, demonstrated prolonged activated partial thromboplastin time (APTT) and increased bleeding. F8 recombinant protein therapy improved APTT and reduced bleeding time in these mice, highlighting the model's potential for evaluating new hemophilia A treatments.