Abstract: Mammalian β-defensins are endogenous cysteine-rich peptide antibiotics that are produced either by epithelial cells lining the respiratory, digestive and urogenital tracts or by granulocytes and macrophages. Here, we examined the expressive tissues of caBD-1 mRNA in camels through RNA in situ hybridization using the digoxigenin-labeled antisense nucleic acid probe which is 42 bp and was designed and synthesized according the known caBD-1 cDNA sequence.The result indicates that caBD-1 mRNA express in the stratified squamous epithelium of dorsal tongue and the columnar epithelium of intestinal crypts.