The present invention provides a monoclonal antibody MF4C4 against human hepatoma marker antigen. This monoclonal antibody is characterized by high specifically binding to the hepatoma antigen. The present invention also provides MF4C4 immunoglobulins, and the fragments and immunological conjugates thereof, and pharmaceutical compositions containing the immunoglobulins, fragments or immunological conjugates. The invention further provides a kit for detecting hepatoma.