A solid-state image pickup device 1A includes an image pickup section 2 having a pixel array P in which a pixel C is two-dimensionally arranged, a lens section 3 having a plurality of lenses 3a arranged on the pixel array P, and an image generating section 4A for generating an image by using an electrical signal SE. The image pickup section 2 has a plurality of the pixel arrays P including one image pickup region T. The image generating section 4A generates the image by averaging the electrical signals SE for each pixel C corresponding to one another among the image pickup regions T, in order to reduce noise present in the electrical signal SE.