To allow even a user who is present in a remote place to improve the efficiency of a plotting work with a CAD by sharing already prepared CAD data through a communication network.
This CAD data managing device is provided with a request processing part 1 for accepting the input of CAD data and management information from terminals 7 and 8 connected through the Internet 6, a CAD data registration processing part 12 for registering the CAD data based on management information, a CAD data storing part 17 for storing the CAD data based on the management information, a CAD data management information storing part 16 for storing the management information, a request processing part 1 for accepting the output request information of the CAD data from the terminals 7 and 8, and CAD data ejection processing parts 13 and 14 for retrieving the CAD data corresponding to the output request information from among the CAD data stored in the CAD data storing part 17 based on the output request information and the management information, and for copying the retrieved CAD data, and for providing the copied CAD data to the output request origin terminal side.