An endoscopic diagnosis system comprising: a light source device for emitting light having a given wavelength range; an endoscope device having an image sensor, and for guiding the light emitted from the light source device, illuminating a subject with illumination light, and imaging reflected light of the illumination light with the image sensor to acquire image signals; a blood amount-oxygen saturation level calculating section for calculating a blood amount and a blood hemoglobin oxygen saturation level of the subject based on the acquired image signals; and an image display device for displaying an oxygen saturation level distribution as pseudo color image based on information on the oxygen saturation level, characterized in that the endoscope device is adapted to acquire three or more image signals including a first image signal corresponding to reflected light having a wavelength range of 460 nm to 480 nm, a second image signal corresponding to reflected light having a wavelength range of 590 nm to 700 nm, and a third image signal corresponding to reflected light having a wavelength range including 540 nm to 580 nm, and the blood amount-oxygen saturation level calculating section comprises a correlation storage having stored therein a correlation between a first signal ratio between the first image signal and the third image signal and a second signal ratio between the second image signal and the third image signal on the one hand and the blood amount and the oxygen saturation level on the other hand, the blood amount-oxygen saturation level calculating section being adapted for calculating the first and the second signal ratio from the first to the third image signal and for calculating information on the blood amount and the oxygen saturation level corresponding to the calculated first and second signal ratios using the correlation stored in the correlation storage. a light source device for emitting light having a given wavelength range; an endoscope device having an image sensor, and for guiding the light emitted from the light source device, illuminating a subject with illumination light, and imaging reflected light of the illumination light with the image sensor to acquire image signals; a blood amount-oxygen saturation level calculating section for calculating a blood amount and a blood hemoglobin oxygen saturation level of the subject based on the acquired image signals; and an image display device for displaying an oxygen saturation level distribution as pseudo color image based on information on the oxygen saturation level, characterized in that the endoscope device is adapted to acquire three or more image signals including a first image signal corresponding to reflected light having a wavelength range of 460 nm to 480 nm, a second image signal corresponding to reflected light having a wavelength range of 590 nm to 700 nm, and a third image signal corresponding to reflected light having a wavelength range including 540 nm to 580 nm, and the blood amount-oxygen saturation level calculating section comprises a correlation storage having stored therein a correlation between a first signal ratio between the first image signal and the third image signal and a second signal ratio between the second image signal and the third image signal on the one hand and the blood amount and the oxygen saturation level on the other hand, the blood amount-oxygen saturation level calculating section being adapted for calculating the first and the second signal ratio from the first to the third image signal and for calculating information on the blood amount and the oxygen saturation level corresponding to the calculated first and second signal ratios using the correlation stored in the correlation storage.