Abstract: In a computer aided design (CAD) system, by distributing managements of a number of concerned parts data to a plurality of work stations (WS), a large scale assembly constructed by a number of parts can be easily designed. There is provided a distributed data CAD system in which a user can easily progress the design of an assembly under distributed circumstances without being aware of the locations of the distributed information. A certain client WS transmits parts numbers to a server WS. The server WS searches a parts construction file by using the parts numbers as keys, thereby obtaining parts construction information and transmitting to the client WS. The client WS checks the parts construction information and when parts shape information exists in a parts shape file connected to its own WS, the client WS searches the file by using the shape names and physical path names as keys, thereby obtaining parts shape information.