The purpose of the present invention is to provide an anti-BMP10 (bone morphogenetic protein-10) antibody, and a therapeutic agent for hypertension and hypertensive diseases, comprising said antibody as an active ingredient. The present invention relates to an anti-BMP10 monoclonal antibody, or an antibody fragment thereof, that binds to human BMP10. The present invention relates to: a therapeutic agent for hypertension and hypertensive diseases that contains a BMP10 and/or BMP9/BMP10 heterodimer antagonist； a diagnostic agent or pharmaceutical composition for diseases in which human BMP10 is involved； an immunological detection method or assay method for human BMP10 using said antagonist； and the use of said antagonist for manufacturing a pharmaceutical composition for the treatment of hypertension and hypertensive diseases.
