The purpose of this poster presentation is to clarify the reasons for the shapes of monuments built to commemorate the victims of the bombing in Japan. During the Second World War, many major cities across Japan were bombed, which resulted in high rates of civilian death. After the war, many monuments were built to commemorate the victims of those bombings. Memorial events have also been held in the affected areas. Although it has been over 70 years since the war ended, memorial events are still held at these monuments annually. In this study, two key stages of visual research were undertaken. First, we photographed monuments established to commemorate the bombing victims in significantly affected areas of Tokyo and Hiroshima. In total, 66 monuments in Tokyo and 83 monuments in Hiroshima were studied. Second, we videoed memorial events that occurred in front of the monuments. A total of 15 memorial events in Tokyo and 15 events in Hiroshima were recorded. We analyzed the materials obtained from our fieldwork, focusing on the shape of those monuments. In this poster presentation, we will clarify how the different shapes of monuments were created according to the religious or secular position of the social group that erected each monument, and how differences in the shapes of monuments influence memorial events.