Background: Hepatic encephalopathy (HE) is a spectrum of reversible neuropsychiatric abnormalities in patients with hepatic disorders. This study aimed to evaluate the effect of critical nursing management on HE patients' outcomes. A quasi experimental research design was utilized. Data were collected from Medical Intensive Care Units at Zagazig University Hospitals. The study was conducted on (30) nurses and (30) patients with HE in the mentioned setting. Three tools were used, a structured interview questionnaire, observational checklists and a structured interview questionnaire for patients. Results of this study showed that, only 16.7% of studied nurses had satisfactory knowledge pre-intervention program then rise up post program to be 66.7%. Percent of nurses' knowledge improvement post intervention program was 41.84%. Only 20.0% of studied nurses' had satisfactory practice level at pre-intervention phase, while upturned at post intervention phase to be 70.0%. Percent of improvement of nurses' practice post intervention program 45.87%. The study displays that majority of patients had family history of liver diseases (83.3%), almost of them had recurrent HE (93.8%). It was found 23.3% of patients had diabetes and hypertension. Finally the main precipitating factors of HE were peritonitis (30.0%), then constipation (26.7%). Conclusion there was a statistical significant improvement in total nurses' knowledge and practice after application of program. Moreover, there was statistically significant difference and improvement of all patients' parameters (dietary history, malnutrition manifestations, anthropometric measures, laboratory investigations and HE assessment tools scores) post program. It was recommended that maintain periodic training and educational programs regarding HE to refreshing and enhance knowledge and practice of nurses.