The present study aimed at investigating the effect of pragmatic activities on developing EFL prospective teachers' critical thinking skills. The study sample consisted of 30 prospective teachers studying at the department of English at the faculty of Education in Damietta University. The sample was divided into two groups: an experimental group (N = 15) and a control one (N = 15). A pre-post critical thinking skills test was implemented on the participants to compare their skills before and after implementing the experiment. The pragmatic tasks were implemented on the experimental group for six weeks while the control group did not receive any instruction except their regular courses at the faculty. The result of the study showed that the effect size of pragmatic tasks was appropriate in developing EFL prospective teachers' critical thinking skills. The study offered suggestions for further research. The results asserted that engaging students in pragmatic learner-centered activities through discussing and analyzing utterances help promote their critical thinking skills.