An apparatus 100 for assessing muscle quality includes a first acquisition unit 20 that acquires bioelectric information including at least one of (i) a resistance component and a reactance component of bioelectrical impedance and (ii) first impedance measured by supplying alternating current at a predetermined low frequency to a living organism and second impedance measured by supplying alternating current at a predetermined high frequency to the living organism; a second acquisition unit 21 that acquires a physical parameter related to physique of the living organism; and a calculation unit 22 that calculates an index in accordance with a proportion, in muscle tissue, of muscle fiber to interstitial tissue based on the physical parameter and on at least one of a first parameter represented as a ratio between the resistance component and the reactance component and a second parameter represented as a ratio between the first impedance and the second impedance.