A solid-state image pickup device wherein, in order to obtain an output of large amplitude from a low-contrast object without using a bottom detecting circuit to thereby increase a capturing rate, an accumulation end is determined when a maximum value signal in a photosensor array reaches a predetermined accumulation end level, and an amplifier circuit unit is provided for amplifying a signal, which is outputted from each of the pixels of the photosensor array, with reference to the maximum value signal of the photosensor array and for outputting the signal.