A medical image processing apparatus, comprising: a medical image acquisition unit adapted to acquire a short wavelength medical image, which is a medical image including a subject image and which is obtained by imaging a subject with light in a shorter wavelength band than a green wavelength band, light in the shorter wavelength band having a peak is in the range of 390 nm to 450 nm; a red blood cell detection unit adapted to detect a red blood cell using the short wavelength medical image; a red blood cell quantity calculation unit adapted to calculate a quantity of red blood cells detected in the short wavelength medical image; a red blood cell movement amount calculation unit adapted to calculate a movement amount of red blood cells detected in the short wavelength medical image; and an index calculation unit adapted to calculate an index indicating a degree of progress of a lesion using the quantity and the movement amount of red blood cells, characterized in that the red blood cell detection unit is adapted to detect a high-frequency, granular, and high-density region having a spatial frequency higher than that of a blood vessel and a tissue contained in mucous membrane, having a granular shape of a pattern that is a fine point, and having a high-density that has a contrast that can be distinguished from the mucous membrane serving as a candidate for a red blood cell eeHusing the short wavelength medical image, and the index calculation unit is adapted to calculate the index indicating the degree of progress of the lesion using the quantity and the movement amount of red blood cells which moves without following the blood vessel. a medical image acquisition unit adapted to acquire a short wavelength medical image, which is a medical image including a subject image and which is obtained by imaging a subject with light in a shorter wavelength band than a green wavelength band, light in the shorter wavelength band having a peak is in the range of 390 nm to 450 nm; a red blood cell detection unit adapted to detect a red blood cell using the short wavelength medical image; a red blood cell quantity calculation unit adapted to calculate a quantity of red blood cells detected in the short wavelength medical image; a red blood cell movement amount calculation unit adapted to calculate a movement amount of red blood cells detected in the short wavelength medical image; and an index calculation unit adapted to calculate an index indicating a degree of progress of a lesion using the quantity and the movement amount of red blood cells, characterized in that the red blood cell detection unit is adapted to detect a high-frequency, granular, and high-density region having a spatial frequency higher than that of a blood vessel and a tissue contained in mucous membrane, having a granular shape of a pattern that is a fine point, and having a high-density that has a contrast that can be distinguished from the mucous membrane serving as a candidate for a red blood cell eeHusing the short wavelength medical image, and the index calculation unit is adapted to calculate the index indicating the degree of progress of the lesion using the quantity and the movement amount of red blood cells which moves without following the blood vessel.