The current study aimed to evaluate the content of the English textbooks taught in Iranian senior high schools. To this purpose, the study relied upon a descriptive survey design. Through a stratified random sampling, a total of 12 senior high schools were selected from the high schools located in Isfahan. To select the teacher participants, a convenience sampling method was employed. Then, a structured questionnaire was administered to the selected teachers and students. The obtained data were statistically analyzed and item analysis revealed that the accessibility and affordability of the textbooks were the most-favored features. However, most of the students wondered whether the textbooks were equipped with supplementary (online and offline) materials. The post-hoc analysis results revealed the significant overall teacher-student disagreement towards the textbooks. Generally, the results showed that there is a need to adapt the teaching materials to the target situation of use. As a practical implication, the findings may urge the developers of the textbooks to launch a modification project in order to get more conscious in developing future textbooks. Moreover, the findings are of use for the teachers of the textbooks as well as the pedagogical policy makers.
