The purpose of the study is to compare and analyze the elementary science textbooks' contents between the United States(Science Horizons) and Korea for teaching the Returnee students. The analyzed contents are the name of chapters, the number of chapters, the page amounts of chapters, the structure of chapters and the studying time of chapters. The results of this study are : 1. Korean science textbook's number is 20. 'Science Horizons' has 6. Korean science textbook's total number of chapter is 58, 'Science Horizons' is 75. Korean science textbook's total number of page is 1,60.3, 'Science Horizons' is 2,106. So 'Science Horizons' has more number of chapter and page than Korean textbooks. 2. The ratio of Korean science textbook's contents is as follows: physical area, 22.4%; chemistry area, 12 1%: biology area, 39.6%; earth science area, 25.9%. But the ratio of 'Science Horizons' science textbook's contents is as follows: physical area,21.3%; chemistry area,4.0%; biology area, 46.7%; earth science area. 28.0%. 3. In case of 'Predicting the Weather' chapter, Korean science textbook has 3 lessons, 17 themes and 11 activities, whereas' Science Horizons' has 5 lessons, 10 themes and 5 activities. 4. The themes or chapters of 'Science Horizons' to propose deeper than Korea are about animals and plants, energy and movement, weather and season. our body, and earth and outer space. In case of Korean textbook are about chemistry area, the rock and volcanic activity and electric circuit. There are some differences between Korean and the United States' elementary science curriculum and textbook's contents. And the returnee students has many troubles to adapt korean science curriculum, textbooks and educational environment,;. Therefore, teachers should know and understand that, and help them.