美國專利暨商標局（the United States Patent and Trademark Office, USPTO)的專利資訊檢索服務網站帶動了專利資料庫出版商的連鎖反應。IBM和MicroPatent也相繼推出了免費的專利資訊檢索網站，使得專利資訊搖身一變成為方便好用的資源，以免費的方式提供給全球各地上網的讀者利用。這項全新的資訊檢索服務也為館員帶來新的契機和挑戰。本文說明專利的特性、重要性、要件和種類，以及專利資訊檢索的步驟，並介紹Internet上的專利資訊服務系統，以利館員和讀者查檢時之參考。

　　　　　The loading of the United States Patent and Trademark Office (USPTO) database on the Internet and World Wide Web (WWW) has set off a chain reaction with other patent database publishers. IBM and MicroPatent are to offer free commercial patent information via the Web. Patent information has never been so accessible, at such low cost， to so many end-users. This new accessibility has offered both opportunities and challenge for librarians. In this paper, the characteristics, importance, requirements and types of patents are discussed. Steps needed to perform a patent subject search are delineated. This studey also describes and different patent databases on the Internet, lists their strengths and weakness, and recommends the best free patent databases.