A living body observation system includes: an illuminating light generation section configured to generate first light and second light an image pickup section a computation section configured to calculate a difference degree indicating a degree of difference between a luminance value of a first image obtained by picking up an image of return light of the first light and a luminance value of a second image obtained by picking up an image of return light of the second light in a same pixel an enhancement processing section configured to enhance a contrast of the pixel in which the difference degree exceeds a threshold relative to a pixel in which the difference degree does not exceed the threshold and an observation image creation section configured to create an observation image by using the first image after the process by the enhancement processing section and the second image.
