Abstract: OBJECTIVE To explore the anti-vitiligo effects of Kebai particles in vitro and in vivo and evaluate the safety of Kebai particles. METHODS The effects of Kebai particles on mouse melanoma cells B16f10 proliferation in vitro was tested by serum pharmacology method. Long term toxicity test were carried out to evaluate the safety of Kebai particles. 50 guinea pigs were randomly divided into 5 groups: normal control group, model control group, high, middle and low dose group of Kebai particles(9.04，4.52，2.26 g·kg^-1·d^-1). The experimental vitiligo guinea pig model was prepared by 7% H₂O₂ for 50 d. Melanin distribution in skin and cholinesterase(CHE), monoamine oxidase(MAO), malondialdehyde(MDA) and tyrosinase(TYR) in blood were determined. RESULTS The results of serum pharmacology experiment showed that medicated serum significantly promoted the proliferation of B16f10 cells in vitro. Long-term toxicity experiment results indicated Kebai particles exhibited no effect on viscera weight of SD rats. Animal experimental data showed that the serum level of MAO and MDA significantly increased in model control group(P<0.05), while the serum level of CHE and TRY significantly decreased in model control group(P<0.01 or 0.05). Compared with the model control group, high dose of Kebai particles significantly decreased the serum content of MDA(P<0.01), high and middle dose of Kebai particles significantly decreased the content of MAO and increased the content of CHE(P<0.05). CONCLUSION Kebai particles show good anti-vitiligo effects, its main mechanism may be related to decrease the contents of serum CHE, MAO and MDA and promote the proliferation of melanocytes.