An endoscope system comprising: a light source; a monitor an endoscope that performs image capturing of an observation target onto which illumination light emitted from the light source is radiated; and a processor device adapted to perform system control and image processing, the endoscope system comprising: an image signal obtaining unit adapted to obtain image signals in a plurality of wavelength ranges obtained by image capturing of the observation target; a baseline information calculation unit adapted to calculate, on the basis of the image signals in the plurality of wavelength ranges, baseline information that is information regarding a light scattering characteristic or a light absorption characteristic of the observation target and that does not depend on specific biological information; a reference baseline information storage unit adapted to store in advance reference baseline information that is a reference for evaluating the baseline information; a baseline correction value calculation unit adapted to calculate a baseline correction value for adjusting the baseline information to the reference baseline information; a first residual liquid information calculation unit adapted to calculate residual liquid information regarding a residual liquid included in the observation target from the baseline correction value, a biological information calculation unit adapted to calculate the specific biological information; characterized in that the first residual liquid information calculation unit includes a residual liquid amount calculation unit adapted to calculate a residual liquid amount of the residual liquid as the residual liquid information, the endoscope system further comprising a second residual liquid image generation unit adapted to generate a second residual liquid image representing the residual liquid information by a numerical value or an indicator, wherein the generated second residual liquid image is displayed on the monitor and the endoscope system further comprises: a biological information calculation accuracy conversion unit adapted to convert the residual liquid information to a calculation accuracy of the specific biological information, wherein the specific biological information is an oxygen saturation level, and the calculation accuracy of the oxygen saturation level is displayed on the monitor. an image signal obtaining unit adapted to obtain image signals in a plurality of wavelength ranges obtained by image capturing of the observation target; a baseline information calculation unit adapted to calculate, on the basis of the image signals in the plurality of wavelength ranges, baseline information that is information regarding a light scattering characteristic or a light absorption characteristic of the observation target and that does not depend on specific biological information; a reference baseline information storage unit adapted to store in advance reference baseline information that is a reference for evaluating the baseline information; a baseline correction value calculation unit adapted to calculate a baseline correction value for adjusting the baseline information to the reference baseline information; a first residual liquid information calculation unit adapted to calculate residual liquid information regarding a residual liquid included in the observation target from the baseline correction value, a biological information calculation unit adapted to calculate the specific biological information; characterized in that the first residual liquid information calculation unit includes a residual liquid amount calculation unit adapted to calculate a residual liquid amount of the residual liquid as the residual liquid information, the endoscope system further comprising a second residual liquid image generation unit adapted to generate a second residual liquid image representing the residual liquid information by a numerical value or an indicator, wherein the generated second residual liquid image is displayed on the monitor and the endoscope system further comprises: a biological information calculation accuracy conversion unit adapted to convert the residual liquid information to a calculation accuracy of the specific biological information, wherein the specific biological information is an oxygen saturation level, and the calculation accuracy of the oxygen saturation level is displayed on the monitor. a biological information calculation accuracy conversion unit adapted to convert the residual liquid information to a calculation accuracy of the specific biological information, wherein the specific biological information is an oxygen saturation level, and the calculation accuracy of the oxygen saturation level is displayed on the monitor.