The purpose this research is to develop QCM (quartz crystal microbalance) biosensor for the determination of haptoglobin. Haptoglobin is an acute-phase protein with a hemoglobin-binding activity and has a potential to be used as a biomarker for infection or cancer. Haptoglobin level in milk has been used for the diagnosis of cow mastitis. In this study, anti-bovine haptoglobin antibody or bovine hemoglobin was chemically immobilized on the surface of the QCM, and the resulting sensor chips were tested for their response to samples containing haptoglobin at different concentrations. Concentration dependent frequency change was observed with both of the sensor chips. Especially, the sensor chip containing anti-bovine haptoglobin antibody showed sufficient sensitivity in the concentrations typically observed in the cows with mastitis.