Objective: In urogynecologic fields, genital atrophy is a common health problem in postmenopausal women. This study aims to evaluate the change of genital atrophy using Light emitting diode (LED) therapy in mouses as a preclinical study. Methods: We performed a prospective evaluation of 20 postmenopausal mouses (control group; n=10, LED group; n=10) which were undergone bilateral ovariectomy from July 2021 to September 2021. We used to the mixed wavelengths of three types as the 460-nm LED (blue), the 592-nm LED (amber), the 630-nm LED (red). Each mouse got LED device (Bellalux, Linkoptics, Gwangu, Korea) on its buttock for 20 minutes for 4 weeks . We got the 1*1cm tissue on both buttock and analyzed to immunohistochemistry analysis using Masson trichrome (MT), hematoxylin and eosin (H&E), smooth muscle antibody (SMA) and vimentin stain. Data were analyzed using SPSS software (version 22; IBM Corp., Armonk, NY, USA). Statistical significance was considered as P< 0.05). The paired t-test analysis was analyzed to compare between no LED group and LED therapy group for 4 weeks after LED treatment Results: We compared to the collagen density and the fibroblast count between no LED group (n=9) and LED therapy group (n=9) for 4 weeks after LED treatment. The mouses of treatment group were treated on LED devices on its buttock for 20 minutes for 4 weeks. On MT stain, mean scale of no therapy group was 127.28 ± 5.03 to be increased to 102.06 ± 6.94 of the LED therapy group (p<0.05). The scale range on MT stain is from 0 to 250; 0 scale means the thickest density of collagen. We check the fibroblast count by eyeball evaluation in each section. The fibroblast count was increased from 51.19 ± 14.71 (control group) to 80.22 ± 31.28 (LED therapy group) after treatment (p<0.05). Conclusion: LED therapy improved to collagen regeneration in mouse model. In the absence of clinical data on postmenopausal women, this provides evidence for a future approach.