Abstract organizational commitment great can support the employee to be slightly pleased by moving the job performance of critical care nurses' power as a result of loyalty to the institute. While it is Low, may cause leaves, conflicts, and sobs which in return harms the institute itself, may result in the failure of trust of the clients. The aims of this study: To identify the relationship between organizational commitment and Job Performance of critical care nurses at Zagazig University Hospitals. Subjects and Methods: Research design: A descriptive correlation research design was used. Setting: Zagazig University Hospitals. Subjects: including 105 critical care nurses. Tools of data collection: Two tools were used for data collection: 1. organizational commitment questionnaire sheet, and 2. six-dimension scale to measure characteristics of nursing job performance. Results: The study indicated that the organizational commitment level reveals that, half (50%) of critical care nurses had a moderate level of commitment, while, 7.3% had a high level of commitment. Although, the job performance level was slightly more than half (54.5 %) had an unsatisfactory job performance level. Conclusion: It is concluded that: there was a highly positive correlation between organizational commitment and job performance among critical care nurses at Zagazig University Hospitals. Recommendation: It is recommended that: in order to improve affective commitment, and nurse's performance the hospitals need to provide support to their nurses and take a strong action to progress a nurses' performance.