Abstract: Protease-activated receptor-2 (PAR-2) is one of the receptor proteins on the membrane of keratinocyte which has been proved involving transportation of melanin granule among melanocyte and keratinocyte. To explore the mechanism of coat color formation of alpaca (Lama pacos). The expression level of PAR-2 mRNA in skin of alpacas with different coat colors was analyzed. The expression levels of PAR-2 mRNA in skin of alpacas with different coat colors were examined by QRT-PCR. The expressive quantity of PAR-2 mRNA in the brown alpaca′s skin tissue was 2.43 times than ones of natural white alpaca. Based on the expression level analysis of PAR-2 mRNA, the result showed that the levels of melanin granules transportation could be one of the mechanisms of alpaca coat color formation.