The objectives of this research are: (1) to describe the features of the existing English textbook used at the agriculture faculty; (2) to describe how the existing English textbooks relevant with the need of the student at the agriculture faculty; (3) to describe specifications of the English textbook expected by the students of agriculture faculty; and (4) to describe the specifications of the theme- based English textbook for agriculture students.
This research and  development  was conducted  into  two  main phases based on Sukmadinata (2006) namely: (1) Exploration phase and (2) Product Development phase. The exploration phase describes: (1) the existing English textbook used at agriculture faculty and (2) the students’ needs toward the content of English teaching. Meanwhile, the Product Development phase informs: (1) the description of theme-based textbook, (2) the students’ need upon the textbook, (3) the result of the product tryout, and (4) the final product of theme-based textbook.
The data in the exploration stage were obtained by conducting literature review, document analysis, interview, observation and questionnaire. The finding showed that there is not any specific English textbook for agriculture in teaching English. The content of the material was too general and teaching English is focused on reading and grammar. On the other hand, the teaching and learning process in the class was still lecturer centered.
The  finding  on  analysis  of  the  existing  textbook  states  the  existing textbook does not concern closely with the aims English teaching and learning at agriculture faculty. The book is not composed based on agriculture students’ need. The materials, situations, topics, and vocabularies of the book provide general English which are not suited to the teaching and learning situation. The activities in reading, listening, speaking, and writing occur in daily situation and there is no one activity conducted in agriculture context. This book is not printed locally in Indonesia. It makes it difficult to find in general bookstore.
The theme-based textbook was developed by considering several aspects namely; (1) objectives and approaches; (2) design and organization; (3) language content;  (4)  language  skills;  (5)  topics  and  (6)  methodology.  The  resulted prototype was validated and reviewed by the content  expert  and  instructional expert. The prototype was tried-out and revised to get the feasible product. The result of observation and Focus Group Discussion involving the researcher, the lecturer, the expert  and the students were used  to  evaluate and  to  revise the prototype into the final product of theme-based textbook. After going through three trials, it could be concluded that the prototype is feasible to be applied as theme-based textbook for agriculture students.