This study aims to explore the impact of critical thinking skills on promotion of intercultural competence among student teachers of an English language teaching program. The participants were 34 student teachers studying English language teaching at BA level. They were equally assigned to two groups as treatment (n=17) and non-treatment (n=17). The student teachers recruited for the experimental group received a 10-week teacher training on the cultivation of critical in intercultural contexts. The data were collected through online tests, rating scales, and a set of reflections. The statistical differences between the experimental and the control groups were confirmed with appropriate effect size calculations to scrutinize the effect of the training. How critical thinking skills and intercultural competence exert an impact on the personal and professional development of teacher candidates were analysed and reported qualitatively through the content analysis of the reflections. According to statistical analysis and student teachers' reflections, critical thinking skills played a complementary and crucial role in fostering intercultural knowledge, awareness, and sensitivity in second language teacher education.