An eyelid detection device that, based on first order differential values and second order differential values of vertical density change at an eyelid boundary in an eye image, shifts the second order differential values upwards by ¼ of the cycle of density change frequency of an eyelid boundary and combines the first order differential values and the second order differential values to compute upper eyelid feature amounts. The eyelid detection device detects a boundary between an upper eyelid and eyeball based on peak points in the vertical direction of the computed upper eyelid feature amounts. Consequently, the boundary between an eyelid and eyeball can be accurately detected even when the eyelid has been applied with makeup.