Expertise of teachers in art is essential for the art education, especially crucial in elementary school in the aspect of the all-round education. However, there are insufficient opportunities to train elementary school teachers to obtain artistic expertise; moreover, the significance of artistic expertise is often neglected. Expanding artistic expertise particularly through the ceramic arts enlightens their insights in arts culture to enrich their lives. Regards to the needs, this study focuses on the development of the ceramic arts training program as a part of the in-service training to enhancing the artistic expertise of elementary school teachers. The result of this study concludes the three criteria for elementary school teacher’s expertise in the arts; ‘identity establishment (elementary teacher’s identity, elementary arts education settlement),’ ‘capability of the ceramic arts and academic knowledge (understanding of ceramic arts culture, ceramic arts theory),’ and ‘practical abilities of ceramic arts (realizing ceramic pieces in a textbook, crafting tableware, crafting traditional pattern in ceramic arts).’ Hence, the program is distinguishable from the existing in-service training program in that it is based on the expertise of elementary school teacher measured through the lens of the ceramic art education.