Back ground: Patient safety is moving up the list of priorities for hospitals and health care delivery systems, but improving safety across a large organization is challenging. Aim of the study was to measure the perception of nurses about factors of safety climate at Assiut University Hospital. The study sample included all nurses general medical & surgical and oncology departments (n=212). The questionnaire sheet consisted of two parts: 1st part related to personal characteristics of the study sample (department, gender, age, qualifications, and years of experience). 2nd part of the questionnaire consisted of 52 items which consider factors of safety climate it divided into ten factors: 1st was related to free communication flow which contains six items; 2nd was related to continuous improvement which contains five items; 3rd that related to reporting / rules compliance which contains three items; 4th was related to patient / family involvement which contains three items; 5th which related to supervisors' safety leadership which contains four items; 6th which related to allied professional ' safety leadership which contains four items; 7th which related to patient safety committee leadership which contains four items; 8th which related to rules/ equipment availability which contains six items; 9th which related to worker attitudes and contains thirteen items; and finally , 10th which related to organizational factors contains five items. The possible responses of this part were: (3) for agree, (2) for neutral and (1) for disagree. Reliability of the tool was done and revealed that the tool is highly reliable (α = 0.92). Results donates there were a highly percentage as regard to most of the safety climate factors (free communication flow, continuous improvement, patient / family involvement, supervisors' safety leadership, allied professional ' safety leadership, worker attitudes, and organizational factors) except the patient safety committee leadership, and rules/ equipment availability in all the selected departments. There were a highly statistically significant differences among the study subjects as regard to factors of safety climate in the following sequence free communication , continuous improvement , patient & family involvement , supervisors' safety leadership, allied professional safety leadership, rules & equipment availability, workers' attitudes, and organizational factors (p<0.001**). While, there were no statistically significant differences as regard to reporting & rules compliance and patient safety committee leadership. Conclusions: There is a highly statistically significant difference among the studied nurses as regard to safety climate at Assiut University Hospital. More than half of nurses agree about factors of safety climate in the studied departments.Recommendations: In the light of the results the study recommended that it is Important for hospital administration to evaluate employees' perception regarding their risk-management programs and patient safety committee and rules and equipment availability. Future hospital studies might examine the effect of safety climate on nurses' job satisfaction, nurses' turnover, productivity rates, accident and incidence rates, and patient satisfaction.