A medical information processing system in an embodiment includes processing circuitry. The processing circuitry acquires an ultrasound image including an observation target and having additional information, positional information indicating a position of an ultrasound probe in a subject at time of collection of the ultrasound image, and a reference image obtained by taking an image of a region including the observation target at a time point other than the time of collection. The processing circuitry generates, based on the positional information, correspondence information in which the ultrasound image and the reference image are associated with each other. The processing circuitry causes an output unit to output the generated correspondence information.
