In recent years, there have been concerns about issues related to communication with others in education and childcare, especially the communication of younger children. One of the things that seem to be important in solving these problems is to raise the assertion of children. In order to nurture assertion, it is necessary to consider programs such as training. At the same time, it is important to assess the assertion of children. Therefore, in this study, the present state of the method for assessing the assertion of children was examined through analyzing the research trend. Since there were a few studies on young children subjects in this field, the study including the research of child subjects was examined.