The purpose of this study was to improve interaction and communication of the elderly with mild dementia by clay-centered group art therapy. The subjects of the study were 6 elderly people over 70 old in the night class of S city E Elderly Day Care Center who participated in a single experimental group was composed. During the research period, from September 5, 2019 to January 16, 2020, the researcher conducted a total of 18 sessions of clay-centered group art therapy once a week. ACIS interaction scale and communication scale (HCS) were used as research tools, and Wilcoxon coded rank verification was performed for data analysis to confirm quantitative changes and qualitative changes by session. As a result, first, as a result of the pre-and post-analysis of the ACIS interaction scale, all sub-domains of the physical domain, information exchange domain, and relationship domain were significant. Second, in the pre-and post-analysis of the communication scale, all sub-factors of communication, such as conversation area, communication area, and behavioral non-verbal aspects, were all significantly differrent. Third, in the process of art therapy, the experimental group showed improved an increase interest in working, acceptance of program topics, increased listening and intimate conversation, and positive verbal and non-verbal expression through repeating clay use. Based on these contents, the significance and limitations of this study were discussed.