Abstract : Critical thinking (CT) is one of the fundamental characteristics of clinical nurses and is widely related with the provision of quality and safe care; yet, the concept of critical thinking presents significant challenges for researchers. Bloom's taxonomy has been utilized to measure critical thinking abilities. Similarly, clinical practice demands the development of all of Bloom's degrees of higher-order thinking skills. To evaluate nurses’ knowledge related to critical thinking concepts (post-test). A quantitative study, utilizing a pre-test and post-test design, a quasi-experimental study was conducted; to determine the impact of an educational program of critical thinking on nurses’ knowledge from the period between 10th October 2020 to 30th August 2022. A non-probability purposive sample was chosen for this study's sample according to the crucial role of nurses in the critical care units in Al-Hillah Teaching Hospitals. The present study confirmed the study’s findings including the majority of nurses of both groups were in middle adulthood, between (25-29) The majority of the participants in the interventional and control group, (77.8%), (66.7%) were female nurses, (50%) of the control group were married and (63.9%) from the interventional group were single. Related to years of experience the results show that the high percentage in both groups 32 (88.9%), and 24(66.7) were with 3 years or less. The majority of participants in the study recorded homogenous characteristics related to demographical items (age, gender, marital status) and employment items (years of experience for nurses), following participation in the educational program on critical thinking, the nurses' knowledge increased. implementation compared to their pre-intervention evaluation as a whole. Nursing staff and nursing management need to work together to provide a conducive atmosphere for critical thinking and innovation, further research can be conducted to Encourage critical thinking as a requirement for job promotion through healthcare organizations.