An object of the present invention is to provide a monoclonal antibody which binds to a human CC chemokine receptor 1 (CCR1) and inhibits activation of the human CCR1, or an antibody fragment there of. The present invention relates to a monoclonal antibody which binds to an extracellular region of a human CCR1 and inhibits activation of the human CCR1 by a human CC chemokine ligand 15 (CCL15), or an antibody fragment thereof, a hybridoma producing the antibody, a nucleic acid having a nucleotide sequence encoding the antibody or the antibody fragment, a transformant cell containing a vector containing the nucleic acid, a method for producing the antibody or the antibody fragment using the hybridoma or the transformant cell; a therapeutic agent and a diagnostic agent containing the antibody or the antibody fragment, and a method for treating and diagnosing a CCR1-related disease using the antibody or the antibody fragment.