Angiogenesis is essential for tumor progression and is regulated by several angiogenic factors such as vascular endothelial growth factor (VEGF). We investigated the expression and distribution of VEGF and its receptor flt-1 in twelve normal canine tissues in six beagle dogs using immunohistochemistry, RT-PCR and real-time RT-PCR. Immunochemical staining showed that both VEGF and flt-1 were expressed in many tissues and their mRNAs were detected in all organs examined by RT-PCR. Levels of VEGF164 and flt-1 mRNA expression were high in tissues containing many intensely immunopositive cells. The expression levels of VEGF164 and flt-1 mRNA tended to be similar. These results indicated that VEGF and flt-1 are closely associated in canine, as in human tissues, and quantifying their mRNAs might be helpful in evaluating angiogenesis.