A device search apparatus able to easily search for and find a device on a different subnet in a network environment where a plurality of subnets are connected together by routers. A client PC as a device search apparatus transmits by multicast a Probe message in which a value representing a search server is set, and extracts from a message received from the search server a URL of a search server on another subnet other than a network to which the client PC is connected. The client PC transmits by unicast, based on the URL of the search server, to the search server on the other subnet a message in which a device type to be searched is set, and extracts from a message received from the search server a URL of a device on the other subnet.