This study aimed to examine gender representation in two developed English language textbooks in Iran, Prospect 3 and Vision 1, which are currently mandatory in secondary schools. Employing the "Criteria for Analysis of the Equality of Gender Representation" scale, a content analysis was conducted based on two main categories: pictorial and verbal elements. The pictorial analysis focused on female visibility in illustrations and images, while the verbal analysis examined components such as subject, object, verb, noun, and pronoun use. The research adopted a qualitative approach within a criterion-driven framework, complemented by quantitative methods for data collection to enhance the validity of findings. Descriptive statistics and chi-square tests were used for the quantitative analysis, while content analysis was applied in the qualitative phase to assess gender representation in the textbooks. The results indicated that gender stereotypes persist in the visual content of these textbooks. However, compared to earlier studies, the verbal sections demonstrated a reduced male bias, suggesting that the textbook authors made attempts to address gender equality. Despite this progress, the findings highlight the ongoing need for further improvements in achieving balanced gender representation in educational materials.