Background: Metacognitive is an essential skill for critical thinking and self-regulation, especially for nursing students. It can help govern thinking, understanding, and problem-solving. This study aimed to evaluate effect of nursing comprehensive skills training program on metacognitive awareness for undergraduate nursing students. Materials and methods: A quasi-experimental design was used. A sample of 70 nursing students were recruited in second year using simple random sampling at Faculty of Nursing -Suez Canal University. Data were collected using nursing student profile questionnaire, and metacognitive awareness inventory. Results: All metacognitive awareness domains show a strong and statistically significant improvement (p < 0.001) as a result of the nursing comprehensive skills. After the intervention, there is a significant average improvement in performance of about 49.37%. Effect sizes ranged from 1.9 to 3.9 (Cohen's d).The findings demonstrate a significant increase of 47.86% in procedural knowledge, 48.85% in conditional knowledge, and 44.46% in declarative knowledge. Additionally, several aspects of cognitive regulation a significant increase of 39.59% to 56.29%. Also, there significant improvement in the level of metacognitive awareness with good level of 78.1 post comprehensive skills training program compared with 1.4% pre comprehensive skills training program. Conclusion: There was a statistically significant improvement in all metacognitive awareness domains after implementation of nursing comprehensive skills training program. Recommendations: Applying Nursing Comprehensive Skills Training Program for improving students' metacognitive awareness for Undergraduate Nursing Students