Despite the role of agency in schools, few researchers have addressed the issue. The present study aims to analyze the relationship between agentic engagement, basic psychological needs, and test anxiety by using structural equation modeling. For this purpose, 289 female students in math-physics and basic sciences were selected as the samples by using multistage cluster sampling. Reeve and Tseng's aspects of students' engagement during learning activity, La Guardia's et al. basic psychological needs, and Ahvaz test anxiety scale were used as data collection tools. The results of structural equation modeling indicated that agentic engagement positively influenced the basic psychological needs such as autonomy, competence, and relatedness while it could negatively affect test anxiety with the mediatory role of basic psychological needs. In conclusion, agentic engagement can be regarded as a critical variable in affecting the basic psychological needs and reducing test anxiety.