In this study, we present a scheduling method for online conferences considering the time difference. Due to COVID-19, many conferences have been held online. At online conferences, presenters give presentations at their original residences. Therefore, it may be necessary to allow presenters to give the presentation during their main activity time if possible. This study proposes a method of scheduling online conferences in consideration of the time difference based on the stream information divided according to research topics. The proposed polynomial time algorithm is divided into two steps. The first step uses a heuristic algorithm for partitioning presentations into sessions, and the second step proposes an integer program to allocate sessions to time slots.