An ultrasound observation apparatus is configured to be able to exchange plural models of ultrasound probes and configured to receive an ultrasound signal from an ultrasound probe connected to the ultrasound observation apparatus. The ultrasound observation apparatus includes: a corrector configured to correct ultrasound data based on the ultrasound signal using first reference data and second reference data, the first reference data being determined by different models of the ultrasound probes to be connected to the ultrasound observation apparatus, the second reference data being determined by individual probes of the same models of the ultrasound probes to be connected to the ultrasound observation apparatus. The corrector is configured to correct the ultrasound signal by performing a calculation on the ultrasound signal using each of the first reference data and the second reference data for each frequency or each distance.
