Abstract: The related information presentation server 10 includes an acquisition unit 12 configured to acquire presentation information indicating lecture content by a lecturer, a detection unit 13 configured to detect a pre-registered keyword included in the presentation information acquired by the acquisition unit 12, and a presentation unit 14 configured to present related information related to the keyword detected by the detection unit 13 to a student. The presentation unit 14 is configured to determine a frequency of presenting the related information to the student based on at least one of a knowledge level of the student regarding the presentation content and a degree of difficulty of the keyword, and present the related information to the student in accordance with the determined frequency.