An abnormal shadow candidate detecting method, including a first smoothing processing process that performs a first smoothing processing of an inputted medical image and using a first smoothing filter a second smoothing processing process that performs a second smoothing processing ON the medical image processed in the first smoothing processing process and using a second smoothing filter an extracting process that extracts a detection object area for an abnormal shadow candidate in a size of a lesion part to be detected and based ON the medical image processed with the first smoothing processing and the medical image processed with the second smoothing processing and an abnormal shadow candidate detecting process that performs detection of the abnormal shadow candidate and in the detection object area extracted from the inputted medical image.
