An accelerated test method evaluates, under accelerated conditions (a temperature T.sub.2 and a voltage V.sub.2), an endurance characteristic of a ferroelectric memory device having a capacitor element including a ferroelectric film under actual operating conditions (a temperature T.sub.1 and a voltage V.sub.1). An acceleration factor (K) required to evaluate the endurance characteristic is derived by using an expression: logK=A(1/V.sub.1-1/V.sub.2)+B(1/V.sub.1T.sub.1-1/V.sub.2T.sub.2) (where each of A and B is a constant).