Flipped Classroom (FC) is an educational approach that has gained considerable attention. It incorporates technology to deliver direct instruction outside of class, while in-class time is limited to contextualized collaborative activities. On the other hand, intrinsic motivation (IM) is a fundamental objective for educators, as it helps learners pursue learning throughout the year. It is the internal drive to engage in learning activities for the sake of personal fulfillment and satisfaction. Recognizing the vital role of IM, the paper investigates the efficacy of flipped learning (FL) in raising students’ IM in grammar courses within the framework of Self-Determination Theory (SDT). A total of forty-one (n= 41) Saudi EFL university students were normally distributed into two groups. The experimental group receives FC instruction, while the control group is taught using traditional explicit instruction. A pretest and a posttest were administered to both groups. Furthermore, a questionnaire was further distributed to the experimental group. The findings of the present quasi-experimental study demonstrate that FC enhances students' IM by providing a student-centered, supportive, positive, and collaborative technology-based environment that promotes their language attainment and satisfies their basic psychological needs for autonomy, competence, and relatedness. Finally, to ensure its successful implementation, it is recommended that teacher training and thorough content planning are vital before implementing FC.