An apparatus according to this invention allows a user to set at least one of desired metabolic circuit information, environmental factor information, and end condition information, changes all of nodes and edges included in the metabolic circuit information or either the nodes or the edges based on at least one of the metabolic circuit information set by simulation condition setting and the environmental factor information until the end condition information set by the simulation condition setting is satisfied, executes a metabolic simulation by a metabolic flux balance analysis, and outputs a result of the simulation executed by simulation execution.