Abstract: A device for measuring the concentration of a slurry solution according to an embodiment of the present invention includes a sensor part including a first sensor for measuring the conductivity of a solution, a second sensor for measuring an ultrasonic wave propagation velocity of the solution, and a third sensor for measuring the absorbance of the solution; and a concentration measurer configured to analyze the conductivity, ultrasonic wave propagation velocity, and absorbance input from the sensor part and measure the concentrations of hydrogen peroxide and a slurry in the solution in real time.