The purpose of this study was to compare the illustrations used in elementary science textbooks of Korea and BSCS in USA, and analyze the types, role, and characteristics of the illustrations. For the analysis, we used 8 elementary science textbooks of the 7th curriculum of science education in Korea from 3rd through 6th grade, and 16 volumes (stage 2 to stage 5) used in BSCS in USA. We examined types of illustrations, including photograph, picture, graphic, cartoon, chart, and their 4 roles such as, motivation, introducing the lesson activity, providing the materials, presenting the learning result. The results were as follows: First, Korean textbooks have more "photograph" type of illustration than BSCS. In BSCS textbooks, diverse types of illustrations were used compared to Korean textbooks. Second, large portion of illustrations in Korean textbooks took a role of providing materials. In BSCS textbooks, the roles of illustrations were more diverse. In BSCS, there were many illustrations to describe students working together with the disabled children, and to explicitly encourage cooperative learning. Considering the findings in this study, educational implications were discussed.