Respective items of a software component, a development task and a required specification, which are enumerated as the requirement for performing the development of software products belonging to a certain category are first registered in recording means. In the registration of the development-task items, when a specific development-task item can be initiated only after the completion of one or more other development-task items at the time of the registration, the specific development-task item is registered together with ordinal information specifying the one or more other development-task items. Then, the operator is allowed to set up the correlations between any two of the software component, the development task and the required specification which have been registered by the item registration function, with respect to each of the items thereof, and information about the correlations is registered in the recording means.