To enable easily obtaining information retrieval result once retrieved by user without performing retrieval again, an information retrieval/information retrieval result providing system includes a network, a user terminal connected to the network, an information retrieval server, information storage server and information sending servers, the information retrieval server and the information storage server being located adjacent with each other. The information retrieval server receives information retrieval request from the user terminal and collecting information including the keyword from a plurality of information sending servers as the information retrieval result, stores storing the information retrieval result depending upon storage request from the user terminal and managing storage period, and transmits and receives electronic mail. The information storage server stores and deletes the information retrieval result under control of the information retrieval server.