Abstract 【Objective】To explore the effect of phased nutritional balance target intervention in critically ill patients receiving mechanical ventilation-assisted therapy.【Methods】A total of 86 patients with severe mechanical ventilation-assisted therapy admitted to our hospital from January 2018 to December 2020 were divided into the control group and the experimental group according to the ratio of 1∶1, with 43 cases in each group. The control group was given clinical routine nutritional support intervention, while the experimental group was given phased nutritional balance target intervention. The nutritional indexes, blood gas analysis results, inflammatory factors and clinical prognostic indicators of the two groups were compared. 【Results】After intervention, the nutritional index and blood gas analysis results of the experimental group were significantly higher than those of the control group(P<0.05). Inflammation factors, mid-intestinal nutritional intolerance rate, Acute Physiology and Chronic Health Evaluation (APACHE Ⅱ) score, lung symptom disappear time, mechanical ventilation time, hospital stay and prognostic indicators in the experimental group were significantly lower than those in the control group. The differences were statistically significant (P<0.05). 【Conclusion】The use of phased nutritional balance target intervention for critically ill patients receiving mechanical ventilation-assisted therapy can significantly improve their nutritional status, reduce the level of inflammation and improve the prognosis of patients.