Objective To explore the effect of subcutaneous cosmetic suture in the suture of lateral episiotomy. Methods From February 2022 to November 2023, 510 parturients with episiotomy admitted to our hospital were randomly divided into reference group and experimental group, with 255 parturients in each group. The reference group underwent extraperineal suture, and the experimental group underwent subcutaneous cosmetic suture. The operation, swelling, pain degree and healing of the two groups were compared. Results The suture time of the experimental group was shorter than that of the reference group, the amount of bleeding was less than that of the reference group, the incision infection rate, moderate to severe swelling rate and moderate to severe pain rate were lower than those of the reference group, and the excellent and good rate of healing was higher than that of the reference group (P <0.05). Conclusion The effect of subcutaneous cosmetic suture inlateral episiotomy is better, which can shorten the suture time, reduce the amount of bleeding, reduce the degree of swelling and pain, and promote wound healing.