An illumination system of an ophthalmologic microscope system projects illumination light onto a patient's eye. A light receiving system guides returning light of the illumination light to an image sensor. A display controller controls a display device to display an image obtained by the image sensor. A magnification changing unit changes display magnification of the image. An interference optical system detects interference light generated from returning light of measurement light from the eye and reference light. An optical scanner is used to scan the eye with the measurement light. An OCT data generation unit processes a detection result of the interference light to generate data. A condition setting unit sets a projection condition of the measurement light in accordance with change in the display magnification. An OCT controller controls the interference optical system and/or the optical scanner based on the projection condition.