The present invention relates to a microbalance-based fine dust measuring device which continuously measures fine dust concentration by automatically replacing filter papers, or performs automatic calibration using a balance weight for calibration, wherein a plurality of concentration measurement filter paper holders, on which filter papers are seated, and a balance weight filter paper holder are seated on a holder mount plate, and wherein the holder mount plate is rotated, thereby replacing the filter paper holders and being mounted on the free end of a vibration tube, the balance weight filter paper holder being for obtaining a mass conversion coefficient, which is the correlation coefficient between the mass of fine dust and the vibration frequency.