Abstract: Objective To investigate the effect of improved oral care in EICU using ventilator to treat patients with clustering nursing. Methods Randomized digital method was used to divide 138 patients with EICU admitted to Ningbo Huamei Hospital into two groups, 69 cases in each group. The control group was given clustering care, and the observation group was given clustered care for improved oral care. The improvement of oral hygiene (bad breath, swollen gum bleeding, oral ulcer) after 3 days and 7 days of nursing care, the number of pathogenic bacteria and the occurrence of ventilator-associated pneumonia (VAP) after nursing, and EICU hospitalization time, mechanical ventilation time in the two groups were compared. Results After 3 days of nursing, the improvement rate of bad breath in the observation group was 55.56%, which was significantly better than that in the control group (30.19%， P<0.05). After 7 days of nursing, the improvement rates of bad breath, swollen gums and oral ulcer in the observation group were 94.44%, 80.56% and 54.17%, which were significantly better than that of the control group (66.04%, 39.47% and 24.00%， all P<0.05). After the nursing, 29 strains of the pathogens were detected in the observation group, and 50 strains were detected in the control group (P<0.05). The hospitalization time and mechanical ventilation time of the EICU in the observation group were significantly shorter than those in the control group (all P<0.05). After the nursing, the incidence of VAP in the observation group was 4.35%, which was significantly lower than that in the control group (17.39%， P<0.05). Conclusion The clustering care with improved oral care can significantly shorten the EICU hospitalization time and mechanical ventilation time in the EICU using ventilator treatment, which can significantly improve the patient's oral hygiene and reduce the incidence of VAP.