Geoengineering is a set of climate technologies for carbon dioxide removal (CDR) and solar radiation management (SRM) that have emerged in the Global North. Given the limited efforts being made to mitigate climate change to achieve the Paris Goals, geoengineering has gained prominence to complement current climate policies. Geoengineering has also emerged in the scientific community, where numerous studies have been conducted. In particular, given the uncertainties and risks of geoengineering, scholars have been interested in the public discourse surrounding geoengineering issues. Despite considerable attention to the discourses of SRM and CDR in the research field, most of it has focused on English-speaking countries in the Global North. This study explores the discourses and actors surrounding geoengineering and discusses how the narratives are being shaped in Japan. The study analyses 61 documents, including policy papers, reports, news articles and academic articles on SRM and CDR, and 11 interviews with relevant actors through discourse and network analysis using an inductive coding scheme. The analysis shows that the Japanese debate on SRM is still underdeveloped and that only researchers have knowledge about the technology. 11 actors have statements on SRM in terms of governance, concerns, implementation and research and development. On the other hand, the debate on CDR, in particular CCS, is active and government, industry and academic groups are very interested in developing and implementing CCS in terms of economic and climate change objectives. Out of 24 relevant CCS actors, 13 actors indicate their position on CCS, such as governance, concerns, implementation, research and development, and business. Several actors belong to international communities that have a transnational influence on the Japanese debate on SRM and CCS, which could affect the narratives and policies. Overall, inadequate and unbalanced power prevents actors from engaging in collective decision-making and agenda-setting on geoengineering. In this context, this study offers four policy recommendations to overcome the challenges surrounding the geoengineering debate in Japan.