Wasteful repetitive tasks are easily reduced in processes to develop complex products. A product development process support system is a system which analyzes dependencies between a plurality of requirements in product development processes belonging to a plurality of layers, and comprises an input reception portion for receiving input of information indicating the dependency between two requirements belonging to adjacent layers and of information indicating the degree of influence of requirements on product development, and dependency derivation portion for deriving the dependency between two arbitrary requirements belonging to the same layer from information indicating the dependencies between the two requirements in question and other requirements received by the input reception portion and from information indicating the degree of influence of the two requirements in question, based on dependency derivation rules established in advance.