[Problem]Provided are a novel diabody type bispecific antibody, the function of which as a bispecific antibody is improved to provide a higher additional value, such as cost saving caused by a reduction in dose, to a drug and a method for producing the same.[Solution]A humanized diabody type bispecific antibody (LH-diabody type bispecific antibody) characterized in that an L-chain is located in the N-terminal side in each polypeptide (LH type) a humanized high-functional bispecific antibody which contains said LH diabody type bispecific antibody a nucleic acid molecule encoding both of two kinds of single-stranded polypeptides constituting said bispecific antibody and a method for producing said antibody which comprises culturing a host cell having been transformed by an expression vector containing said nucleic acid molecule.
