The purpose of this study was to develop a digital textbook on metabolism and digestion system using 5E learning cycle model in high school Life Science Ι. The iBooks Author was used as an authoring tool to develop the digital textbook. The digital textbook was composed of 10 periods of lessons on metabolism, digestive organ, and digestive enzyme. The digital textbook was also involved in diverse digital contents using interactive and motivation-evoking tools, such as drawing, gallery, media, dialogue-based images, highlight, and form-bulder widgets. The developed digital contents have been provided abundant multimedia and interactive simulation materials for student s better understanding on biological concepts of the topics. The results were shown that students were highly motivated in the digital contents, specifically in the given pictures and video clips. The digital textbook has been also evaluated as an intuitive and interactive teaching and learning materials by teachers and students. This study might be suggested that the digital textbook can be an alternative textbook for future generation which is sensitive to digital environment.