The bamboo leaf flavonoids nanoparticles(BLFN) were prepared by ionic cross-linking method, using turnip polysaccharide as a carrier, ε-polylysine as a crosslinking agent. The particle diameter is about 400 nm, particle size distribution is concentrated and of good dispersibility. After B16 melanoma cells were treated with BLFN, the cell proliferation rate, tyrosinase activity and melanin content were measured respectively, and the effects of BLFN on B16 cells were compared with that of arbutin. Results showed that the tyrosinase activity, the synthesis of melanin and proliferation rate of B16 cells were all negatively related to the drugs concentration. When the concentration is 100 μg/mL, the inhibition rate reached at 69.68%, 62.35% and 59.14% respectively, showing significant difference as compared to arbutin (p <0.05). In conclusion, BLFN is a potential substitute for arbutin which has been proved to be an effective inhibitor for melanin synthesis. Meanwhile, the nanoparticle is a combination of various natural products with lower toxicity, which ensuring broad prospects in its application as whitening products.