A method for obtaining an index for non-invasively identifying NASH is provided. A NASH determination method comprising a method for acquiring free radical consumption speed information by non-invasively detecting a redox reaction in a liver of a test animal in real time, comprises a step (1) of obtaining free radical concentration data by applying a magnetic resonance method to the liver as a measurement target after administering a probe into a body a step (2) of obtaining imaging information by processing the obtained free radical concentration data and a step (3) of obtaining a free radical consumption speed by kinetically measuring the imaging information over time, and comprises a step of determining whether or not the test animal has NASH, based on the free radical consumption speed information obtained through application to the test animal.
