Objective To investigate the effect of Parks incision cosmetic correction surgery under microscope in the treatment of adult strabismus. Methods A total of 55 adult strabismus patients admitted to our hospital from February 2022 to February 2023 were selected as the research objects. According to different surgical methods, they were divided into control group (28 patients) and observation group (27 patients). The control group was treated with limbal trapezoidal conjunctival flap incision correction, and the observation group was treated with Parks incision cosmetic correction surgery under microscope. The operation related indexes, pain degree, tear film function, clinical efficacy and complications were compared between the two groups. Results The operation time and blood loss in the observation group were better than those in the control group (P <0.05). The VAS score of the observation group was lower than that of the control group (P <0.05). The length of tear immersion in the observation group was higher than that in the control group, and the corneal fluorescence staining score was lower than that in the control group (P <0.05). The total effective rate of the observation group was higher than that of the control group (P <0.05). The incidence of complications of the observation group was lower than that of the control group (P <0.05). Conclusion The treatment of adult strabismus with Parks incision cosmetic correction surgery under microscope is effective, which can effectively improve the patient's condition, accelerate the recovery of the patient's eye position, improve the tear film function, reduce the degree of postoperative pain and the risk of complications, and has a high application advantage.