To analyze the effect and safety of microplastic injection of type A botulinum toxin combined with sodium hyaluronate in facial contour remodeling. Methods A total of 128 patients who received facial contour remodeling in Xi'an International Medical Center Hospital from January 2020 to March 2023 were selected as the study objects, and were divided into observation group (n =64) and control group (n =64) according to different treatment methods. The facial contour of the two groups was reconstructed, the control group was injected with type A botulinum toxin combined with autologous fat filling, and the observation group was injected with type A botulinum toxin combined with sodium hyaluronate. The changes of the lower facial contour, the effect of wrinkles removal, treatment and adverse reactions were compared between the two groups. Results After treatment, the changes of subfacial width, subfacial length, midfacial length, subfacial chin angle and facial ratio were better than before treatment, and the changes of subfacial contours in observation group were better than those in control group (P <0.05). After 3 months of treatment, the total effective rate of the control group was better than that of the observation group (P <0.05). The hospitalization time of observation group was shorter than control group, and the treatment cost was less than control group (P <0.05). There was no significant difference in the incidence of adverse reactions of facial stiffness, facial asymmetry, sodium hyaluronate embolism and uneven facial bump between the observation group and the control group (P >0.05). Conclusion Autologous fat filling can improve patients' static wrinkles, type A botulinum toxin can improve patients' dynamic wrinkles, and has a better effect on facial contour improvement, which can effectively shorten treatment time and reduce treatment cost without increasing adverse reactions, and is more cost-effective.