An optical scanning observation system includes: an endoscope having an optical scanning portion for scanning an object; a drive signal generation portion configured to generate a drive signal and supply the signal to the optical scanning portion; an electric-current measurement portion configured to measure an electric current value of the drive signal; a first storage portion in which a measured electric current value when the temperature of the optical scanning portion is a predetermined temperature is stored; a second storage portion in which a plurality of parameters that are set according to the size of the measured electric current value are stored; and a correction processing portion configured to correct a scanning range of the endoscope by reading in from the second storage portion a parameter that corresponds to the size of the measured electric current value read in from the first storage portion.