To enable the browser of a home page to overlook the content information of an updated home page.

This content information output device 100 is connected to a network 150, and configured to detect the update of a desired home page, and to output the updated content information. The content information output device 100 is provided with a content information acquiring part 102 for acquiring the content information of a homage page (162a, 162b) to be monitored reserved in a Web server(160a, 160b) connected to a network 150, an update detecting part 106 for detecting the update of the home page to be monitored and an output part 115 for outputting the updated contents information of the home page when the update of the home page is detected by the update detecting part 106.