Objective To explore the effect of modified episiotomy suture on improving the prognosis of patients with episiotomy. Methods A total of 369 patients with lateral episiotomy admitted to Jurong People's Hospital from March 2022 to August 2023 were randomly divided into experimental group (n =185) and reference group (n =184). The reference group was treated with conventional episiotomy suture, and the experimental group was treated with modified episiotomy suture. The operation condition, pain degree, incision healing and satisfaction were compared between the two groups. Results The amount of bleeding, healing time and infection rate in the experimental group were better than those in the reference group (P <0.05). The VAS score of the experimental group at 24, 48 and 72 h after operation was lower than that of the reference group (P <0.05). The incision healing of the experimental group was better than that of the reference group (P <0.05). The satisfaction of the experimental group was higher than that of the reference group (P <0.05). Conclusion Modified episiotomy suture can improve the operation of patients with episiotomy, reduce the degree of pain, promote wound healing and improve satisfaction.