PURPOSE: To automatically decide a process result by generating simulation data which are not fixed (flexible evaluation of program to be evaluated).

CONSTITUTION: A scenario storage part 20 stores a scenario determining the outline of the evaluation order of the program 100 to be evaluated. An input data storage part 202 stores input data sets corresponding to respective events. An expected value storage part 205 stores expected value sets corresponding to the respective events. An execution means 201 generates simulation data by referring to the scenario storage part 204 and input data storage part 202 and supplies the simulation data as an input to the program 100 to be evaluated. A decision means 203 compares a process result outputted from the program 100 to be evaluated with the expected value corresponding to the process result to decide whether or not the corresponding process result matches the expected value.