Abstract This research aimed at studying the impact of a project-based blended learning (PBBL) program on enhancing EFL secondary stage Al-Azhar students' psychological flow. The participants of this research were (58) second year Al-Azhar secondary stage students at Fisha Banah and Meet Masoud Secondary Institutes, Aga, Dakahlia, Egypt. The research adopted the quasi-experimental design using two groups: an experimental group (n= 28) and a control one (n= 30). To collect data, the researcher used a psychological flow scale consisted of thirty-six items. The researcher taught both groups: the experimental group was taught through the PBBL program, while the control group was taught through the regular method of teaching. Research results revealed that there was a statistically significant difference between the mean score of the experimental group and the control group in the psychological flow scale in favor of the experimental group. Moreover, the effect size of the PBBL program was found to be high. Thus, this research recommended embedding the psychological flow dimensions during the teaching and learning processes.   Key words: Project-based blended learning, psychological flow, EFL