To evaluate the hair-blackening efficacy of stewed Polygoni Multiflori Radix(PMR) and investigate its mechanism of action.Methods:A mouse model of white hair was established，and the hair-blackening effect of stewed PMR were assessed by measuring the area of white hair in new hair growth regions，using hematoxylin-eosin(HE) staining，and analyzing plasma tyrosinase(TYR) levels.Network pharmacology and immunofluorescence techniques were employed to explore the mechanism of action.Results:Compared to the sham operation group，the model group exhibited a significant increase in the area of white hair on the back，a notable reduction in melanocyte-containing hair follicles in the skin tissue，and a decrease in plasma TYR levels.Compared with the model group，treatment with positive control，processed PMR(medium and high doses)，and stewed PMR(low，medium，and high doses) significantly reduced the white hair area in mice.Processed and stewed PMR at low，medium，and high doses significantly increased the number of melanocyte-containing hair follicles，while the processed and stewed PMR at a high dose notably increased plasma TYR levels.Under the same dose of crude herb，compared with the processed PMR，the stewed PMR at a medium dose significantly increased the number of melanocyte-containing hair follicles，and stewed PMR at both low and high doses increased plasma TYR levels.Network pharmacology analysis indicated that the hair-blackening effect of stewed PMR involved melanin production and Wnt signaling pathways.Immunofluorescence results showed that，compared with the sham operation group，the model group had significantly reduced expression levels of lymphoid enhancer-binding factor 1(LEF1) and TYR in skin tissue，while the stewed PMR groups exhibited increased levels of LEF1 and TYR expression.Conclusion:Stewed PMR has a notable effect on improving the white hair model in mice，and its mechanism may be related to the upregulation of LEF1 and TYR expression levels.