The present invention enables a predetermined user and a customer of the predetermined user to be easily associated, and to engage in communication having a shared web page, without installing dedicated software or the like.A communication support device 1 generates, with a generating processor 13, a web page that is deployed on a mutually associated user terminal 2 and customer terminal 3, the web page having a shared web page that is shared by the user and the customer displayed within a predetermined display area. A transition history acquirer 14 acquires a transition history of the shared web pages from the mutually associated user terminal 2 and customer terminal 3, and on the basis of the transition history, when there is a transition of the shared web page on one of the mutually associated user terminal 2 or customer terminal 3, a synchronization processor 15 synchronizes the shared web page on the other terminal with a post-transition web page as a new shared web page.