In order to efficiently create a library of characteristic values of a low hierarchical circuit, which library is used in operation verification of circuitry including low hierarchical circuitry and high hierarchical circuitry, so that the time period necessary to create a library is considerably reduced, the present apparatus includes a recognizing unit which recognizes a simulation object circuit in circuitry; a simulation unit which simulates the simulation object circuit; and a creating unit which creates a library of characteristic values of the simulation object circuit based on the simulation result obtained by said simulation unit.