This study is an exploratory work to identify the Enneagram personality types of children. The purpose is to develop an observation measure which can be applied to the analysis of childhood personality types, and verify the validity of it. The observation measure was designed on the basis of the nine Enneagram personality types. It consists of nine factors, i.e. type 1, type 2, type 3, type 4, type 5, type 6, type 7, type 8 and type 9. To accomplish the purpose of the study, through literature review, empirical data collection and interviews with professionals, a conceptual model was constructed. The expectation validity of the model was then verified. The result of this study suggests the following: First, the observation measure and the items of the inventory developed in this study was based both on theoretical discussions and on the analysis of data collected from the children who participated in Enneagram workshops. Second, the observation measure of this study is composed of items which are easy for children to understand and therefore convenient when used for children. Third, the observation measure developed in this study is expected to be useful not only for children themselves but also for teachers and parents. The measure could be of help in enhancing their understandings of children, which will enable them to give substantive help to children in school or family settings.