A recombinant antibody or the antibody fragment thereof which specifically reacts with an extracellular domain of human CCR4; a DNA which encodes the recombinant antibody or the antibody fragment thereof; a method for producing the recombinant antibody or the antibody fragment thereof; a method for immunologically detecting CCR4, a method for immunologically detecting a cell which expressed CCR4 on the cell surface, a method for depleting a cell which expresses CCR4 on the cell surface, and a method for inhibiting production of Th2 cytokine, which comprise using the recombinant antibody according or antibody fragment thereof; a therapeutic or diagnostic agent for Th2-mediated immune diseases; and a therapeutic or diagnostic agent for a blood cancer.