The slit lamp microscope is capable of easily adjusting a slit-light and a backlight. The slit lamp microscope comprises: a slit lamp for emitting a slit-light; a mirror unit having a reflecting mirror or a prism, which reflects the slit-light emitted from the slit lamp toward an eye of an examinee; a microscope unit for observing the eye of the examinee; and a backlight source for emitting a backlight, which illuminates a circumference of the slit-light, toward the eye of the examinee. The backlight source is provided to the mirror unit.