Risk factor of cardiac arrest among ill patient has as a risk factors for sudden death, through cardiac arrhythmias, tension pneumothorax ,shock, hypoglycemia ,Myocardial infarction (MI), pulmonary embolism, or edema ,hypothermia and drug toxins, At Assuit University Hospital major risk factor of cardiac arrest as diabetic ketoacidosis Subjects and Method: Study was executed in the following: Coronary, Trauma, post, Elraghy ,and General intensive care units. The study sample consisted of all patients predisposing to cardiac arrest admitted to intensive care units within 6 months period. Three tools were utilized for data collection: tool (one):"Patient's characteristics and clinical data ”, tool (two): "cardiac arrest patient tool (three ) Risk factor of cardiac arrest . Results: Major risk factor for cardiac arrest patients among critically ill in the above mentioned setting at Assuit Hospital was 130 patients who predisposing for cardiac arrest. About (18.5%) with diabetic keto acidosis, and (17.7%) with chronic obstructive pulmonary disease .were expose to cardiac arrest Conclusion: Risk factors of cardiac arrest have been identified as(diabetic keto acidosis ,is most common certified in tables to help predict the cardiac arrest by alerting a clinical response Recommendations: Monitoring risk factors for cardiac arrest should be required to allow for the early detection and management.