The present invention relates to a method and system for providing ‘；diagnosis-aiding information’；, the method and system being capable of diagnosing cancer and the like of a patient by using medical imaging. According to the present invention, the system for providing the diagnosis-aiding information comprises: the image receiving part for receiving the medical images acquired in the first energy band and the medical images acquired in the second energy band； and the ‘；analysis- and diagnosis-aiding information providing part for providing diagnosis-aiding information generated by analyzing the medical image acquired in the first energy band and the medical image acquired in the second energy band, wherein the ‘；analysis and diagnosis-aid information providing unit’； provides the diagnosis-aiding information by measuring the HU values in the region of interest (ROI) of the medical images acquired in the first energy band and the medical images acquired in the second energy band and comparing the HU values of the ROI of two medical images.
