A device management system is provided which is used in a client/server architecture system, enabling safe sharing of a device without compromising user convenience. In a case where the device which is connected to a client is accessed from a server, in order that the device connected to the client can be used from the server by merely connecting the device to the client without performing another operation, a filter is provided on the client side, and a pseudo bus driver is provided on the server side. The filter in the client exclusively controls client operations to the device and server operations to the device. The pseudo bus driver virtually functions as a device driver between a communication unit for the client and the application in the server.