Objective: To observe the efficacy of trehalose eye drops on experimental dry eye rat with removal of inside and outside lacrimal glands. Methods: A total of 30 SD rats were randomly divided into a normal group, a control group, and an experimental group, with 10 rats for each group (20 eyes). The normal group was not treated, and the experimental group and the control group were made into a dry eye animal model by removing the main lacrimal gland of the rat. The control group and the experimental group were given with normal saline and trehalose eye drops once a week after the completion of modeling, 4 times a day for 4 weeks. Shirmer I test and fluorescence staining test were carded before and 1, 2, 3, and 5 weeks after modeling. After 5 weeks of modeling, the rats were sacrificed and the expression of Bcl-2 and Bax apoptosis protein in conjunctival epithelial cells was detected by immunohistochemistry in order to observe the relationship between apoptosis of conjunctival epithelial cells and dry eye lesions and tissue damage in dry eye animal models. Results: Schirme I test results showed that there was no significant difference between the control group and the experimental group (P > 0.05) except for the 5th week after operation (P < 0.05). There was a statistical difference between the two groups and the normal group at each time point after surgery (P < 0.05). At the first week after modeling, the corneal fluorescence staining scores of the control group and the experimental group were significantly higher than those of the normal group. After the second week after surgery, there was no significant difference between the control group and the experimental group (P > 0.05). The prolongation of time, the 3 week and the 5th week after surgery, the difference between the two groups was statistically significant (P < 0.05), and the score of the experimental group was smaller than the control group. The immunohistochemical results of conjunctival epithelial cells showed that the number of Bax protein positive cells in the normal conjunctival epithelial cells was less than that in the control group and the experimental group. The difference between the normal group and the control group was statistically significant (P < 0.05). There was no significant difference between the two groups (P > 0.05). There was a large amount of Bcl-2 protein in the normal group, which was more than the experimental group. The difference was not statistically significant (P > 0.05), which was more than the control group. The difference was statistically significant (P < 0.05); a large amount of Bax protein was positively expressed in the cytoplasm and brownish-yellow particles in the conjunctival epithelial cells of the control group. The positive expression of Bax protein in the experimental group was significantly less than that in the control group, and the difference was statistically significant (P < 0.05). A large amount of Bcl-2 protein was positively expressed in the conjunctival epithelial cells of the experimental group, and the expression of Bcl-2 protein in the control group was significantly decreased compared with the experimental group (P < 0.05).Conclusion: Trehalose eye drops can reduce epithelial detachment of the cornea and have a protective effect on conjunctival epithelial cells, which can antagonize the apoptosis of conjunctival epithelial cells, thereby enhancing the keratoconjunctival barrier function and improving the ocular surface epithelium caused bydryness. The potential clinical application of trehalose solution for ocular surface epithelial diseases and provide treatment options for ocular surface diseases, such as dry eye.