The current scales for self-blame are not suitable for school bullying scenarios and most lack validity. This study used a self-developed scale to measure bullied victims' tendency to self-blame and further examined whether victims and bully/victims exhibited different tendencies toward self-blame under both bullied and generalized scenarios. The study consisted of 1,320 student participants from grades five to nine. The research instrument was a self-constructed bullied-victim self-blame scale (BSS), and the results were analyzed using the Rasch rating scale model. The Rasch results showed strong evidence of BSS reliability and validity. The results indicated that participants' self-blaming tendency scores were positively correlated with depression (r = 0.31). In addition, participants' self-blaming scores in relational bullying were higher than those in verbal and physical bullying. The self-blaming tendency of bully/victims under bullied scenarios was higher than that of victims, but no difference was found between bully/victims and victims for generalised scenarios. The participants' tendency to self-blame under generalised scenarios was significantly higher than under bullied scenarios. The tendencies of various roles to self-blame under different scenarios and the self-blaming counselling strategies for victims are discussed at the end of this study.