Abstract: Background: Concept mapping aims to enhance pediatric nursing students' knowledge and skill acquisition by promoting advanced critical thinking across various scenarios. Purpose of this study was to assess the effect of concept mapping on critical thinking of pediatric nursing students caring for children with pneumonia. A quasi-experimental design (study and control groups) was used. Setting: It was conducted in the pediatric nursing department at faculty of nursing at Menoufia University. Sampling: A convenient sample 230 third-year undergraduate pediatric nursing students was selected. Instruments: Three instruments for data collection were used; instrument one was characteristic of students self-administered questionnaire for pediatric nursing students, instrument two was Watson Glaser Critical Thinking and instrument three was nursing process evaluation structured questionnaire. The results of this study showed that students in the study group showed improvement in mean of critical thinking abilities on posttest 52.73 ± 1.91compared to 18.73± 6.45 on pretest. So there was a highly statistical significant difference between posttest and pretest (p<.001). Meanwhile mean of critical thinking of students in the study group was 52.73 ± 1.91 compared to 26.32 ± 17.27 in the control group. So there was a highly statistical significant difference between study and control group on posttest (p<.001). Conclusion: The study concluded that concept mapping has a positive effect on improving and motivating critical thinking skills among pediatric nursing students. Recommendations: this study recommended that nursing students should be encouraged to use concept mapping strategy in nursing education in order to have higher level of critical thinking skills.