The purpose of this study is to develop digital textbooks on ‘excretion on filtration’, a part of Science in junior high school, using the learning model for biomimicry-based convergence. The digital textbook was used the iBooks Author as the authoring tool with the gallery widget, video widget, texting image widget and other basic functions. Three phases of learning processes in the digital textbook were composed of scientific exploration, convergent design, and convergent creation, which are provided students to facilitate learning for self-directed and active collaboration. In the scientific exploration stage, the students are able to build knowledge on the principle of excretion in kidney and production of a simple water purifier using filtration principle. In the convergent design stage, the students learn about 3D modeling to design a products using 3D printer. In the convergent creation, the students make a actual 3D objects using the 3D printer. Through designing the digital textbooks on excretion filtration, this study are expected students to raise the level of interest and immersive experience on the topic. Furthermore, the learning process of the digital textbook is expected to improve students’ convergent thinking skills.