Objective To explore the effect of preventive nursing measures in patients with congenital ptosis and its influence on the occurrence of postoperative keratitis. Methods A total of 58 patients with congenital ptosis admitted to our hospital from September 2021 to September 2023 were randomly divided into reference group and intervention group, with 29 patients in each group. The reference group was given routine nursing measures, and the intervention group was given preventive nursing measures on the basis of the reference group. The incidence of postoperative keratitis, eyelid condition, treatment effect, quality of life and nursing satisfaction were compared between the two groups. Results The incidence of keratitis in the intervention group was 3.45%, which was lower than 24.14% in the reference group (P <0.05). The eyelid height and eyelid appearance score of the intervention group were higher than those of the reference group (P <0.05). The total effective rate of treatment in the intervention group was 96.55%, which was higher than 79.31% in the reference group (P <0.05). The scores of all dimensions of quality of life in the intervention group were higher than those in the reference group (P <0.05). The nursing satisfaction of the intervention group was 96.55%, which was higher than 72.41% of the reference group (P <0.05). Conclusion The occurrence of postoperative keratitis in patients with congenital ptosis is related to many factors. The implementation of preventive nursing measures can effectively reduce the incidence of keratitis, improve nursing satisfaction, improve the quality of life of patients.