The present invention relates to human monoclonal antibodies derived from human B cells present in the blood of patients who had recovered from infection with influenza A viruses, wherein the monoclonal antibodies have neutralizing activity against influenza A viruses. The anti-influenza A virus monoclonal antibody of the present invention has binding and neutralizing activities against at least one influenza A virus selected from the group consisting of influenza A virus H1, H2 and H5 subtypes, and thus it is useful for the prevention and treatment of a disease caused by the influenza A virus and is also useful for diagnosis of influenza A virus infection.