This article explores the history and cultural importance of blood type discrimination in Japan. It explains how the belief originated during World War II and has become part of mainstream culture, as well as how it is perceived by the Japanese today. It also discusses common misconceptions about blood type discrimination, such as employers using it to determine who they should hire or promote, and explains its link with astrology. Finally, it looks at whether or not Japanese society actually discriminates on blood type and concludes that there is no evidence to suggest that this occurs.