A cell observation device is provided with a reflection interference shutter 106A which adjusts a light quantity of light emitted from a reflection interference measurement light source 106, a quantitative phase shutter 105A which adjusts a light quantity of light emitted from a quantitative phase measurement light source, a camera 110 which images reflected light from the reflection interference measurement light source 106 to generate a reflection interference image and which images transmitted light from a quantitative phase measurement light source 105 to generate a quantitative phase image, and a first extraction unit 204 and a second extraction unit 205 which extract first and second parameters from the reflection interference image generated by the camera 110. During generation of the reflection interference image, the quantitative phase shutter 105A blocks the light from the quantitative phase measurement light source 105. During generation of the quantitative phase image, the reflection interference shutter 106A blocks the light from the reflection interference measurement light source 106.