Objective To observe the effect of micro-focusing ultrasound in facial skin aging and beauty. Methods A total of 68 patients with facial skin aging and beauty treated in our hospital from January 2023 to January 2024 were selected as the research objects. They were divided into control group and observation group by random number table method, with 34 patients in each group. The control group was treated with hyaluronic acid water light injection, and the observation group was treated with microfocus ultrasound on the basis of the control group. The cosmetic effect, facial wrinkles (WSRS) score, global aesthetic improvement (GAIS) score, pain (VAS) score, skin index, complication rate, and treatment satisfaction were compared between the two groups. Results The total effective rate of treatment in the observation group was 94.12%, which was higher than 82.35% in the control group (P <0.05). The scores of WSRS, GAIS and VAS in the two groups after treatment were lower than those before treatment, and those in the observation group were lower than the control group (P <0.05). After treatment, the elasticity and water content of the two groups were higher than those before treatment, the skin loss, sebum content, heme and melanin were lower than those before treatment, and the elasticity and water content of the observation group were higher than those of the control group, the skin loss, sebum content, heme and melanin were lower than those of the control group (P <0.05). The incidence of adverse reactions in the observation group was 8.82%, which was lower than 20.59% in the control group (P <0.05). The treatment satisfaction of the observation group was 100.00%, which was higher than 85.29% of the control group (P <0.05). Conclusion Micro-focusing ultrasound has a definite cosmetic effect on facial skin aging, which can improve the total effective rate of treatment, improve skin condition, reduce facial wrinkles and pain scores, prevent complications, and improve treatment satisfaction. It has important clinical application value.