Objective To analyze the analgesic effect of dexmedetomidine combined with sufentanil on children with extensive burn after eschar shaving and skin grafting. Methods From January 2021 to December 2023, 74 children with extensive burn who underwent eschar shaving and skin grafting in Dongming County Maternal and Child Health Care Hospital were selected as the research objects. They were divided into control group and observation group by random number table method, with 37 children in each group. The control group was given sufentanil for postoperative analgesia, and the observation group was given dexmedetomidine combined with sufentanil for postoperative pain. The postoperative sedation, analgesic effect and adverse reactions were compared between the two groups. Results The Ramsay sedation score of the observation group was higher than that of the control group at 2, 6, 12, 24 and 48 h after operation, and the difference was statistically significant (P <0.05). The FACES pain scores of the observation group at 2, 6, 12, 24 and 48 h after operation were lower than those of the control group, and the differences were statistically significant (P <0.05). The incidence of adverse reactions in the observation group was 5.41%, which was lower than 18.92% in the control group, and the difference was statistically significant (P <0.05). Conclusion Dexmedetomidine+sufentanil can effectively improve the sedative and analgesic effects and reduce the incidence of adverse reactions in children with large area burns treated by eschar shaving and skin grafting.