Objective To study the application effect of ultrasonic scalpel in middle and lower facial cosmetic surgery. Methods A total of 61 patients who underwent middle and lower facial cosmetic surgery in our hospital from January to September 2021 were selected as the research objects and treated with ultrasonic scalpel. The total clinical effective rate, pain grade, skin symptom score and incidence of adverse reactions at different time points after treatment were observed. Results The total effective rate of 3 months after treatment was higher than that of 1 month after treatment, and the difference was statistically significant (P<0.05). On the 7th day after treatment, pain grades Ⅰ and Ⅱ accounted for more than grade Ⅲ, and pain grade Ⅰ accounted for more than grade Ⅱ (P<0.05). The scores of tight skin, smooth skin, bright skin, wrinkles, nasolabial sulcus and pores 3 months after treatment were higher than those before treatment (P<0.05). After 3 months of follow-up, the incidence of adverse reactions in 61 patients was 9.84%. Conclusion Ultrasound scalpel plays a prominent role in the middle and lower facial cosmetic surgery, which can improve and brighten the skin color, make the skin delicate, smooth, and reduce the pores, and has light pain and high safety.