Objective To compare the effects of alfentanil and sufentanil in intravenous anesthesia for the middle and lower facial liposuction. Methods From April 2022 to April 2024, 60 patients who underwent middle and lower facial liposuction in Xi'an Yanta Johnson Star Children's Hospital were selected as the research objects. According to the different anesthesia schemes, they were divided into control group and observation group, with 30 patients in each group. The control group was anesthetized with sufentanil, and the observation group was anesthetized with alfentanil. The fluctuation of vital signs, anesthesia and complications were compared between the two groups. Results The mean arterial pressure at T2, T3, T4 and T5 in the observation group was higher than that in the control group (P <0.05). The heart rate of the observation group at T2, T3, T4 and T5 was lower than that of the control group (P <0.05). The dosage of etomidate in the observation group was lower than that in the control group, and the onset time of anesthesia, recovery time of consciousness and awake time of patients were shorter than those in the control group (P <0.05). The incidence of complications in the observation group was 13.33%, which was lower than 36.67% in the control group (P <0.05). Conclusion For patients with middle and lower facial liposuction, both alfentanil and sufentanil in intravenous anesthesia can achieve certain anesthetic effects, but the overall anesthetic effect and safety of alfentanil are better than those of sufentanil, which is conducive to maintaining the stability of patients' vital signs.