PURPOSE: To estimate the photosensitivity of the photosensitive body at the stage of the formation of a charge generating layer by measuring the light reflectivity of the surface of a conductive base and the light reflectivity of the surface of the base body through the charge generating layer.

CONSTITUTION: The surface of the conductive base body is irradiated with light having specific wavelength first and the reflectivity R1 is measured. Then the charge generating layer is formed on the base body by coating, the base body surface is irradiated with light having the same wavelength through the charge generating layer, and the reflectivity R2 is measured. Then the photosensitivity of the photosensitive body which is obtained from the value of the reflectivity difference R1-R2 is estimated and evaluated. The difference R1-R2 is larger and larger as the quantity of half-attenuation exposure is smaller and smaller, namely, as the photosensitivity is higher and higher. Therefore, the photosensitivity of the photosensitive body which is obtained at the stage of the formation of the charge generating layer can be estimated and evaluated.