We recently developed a high efficiency expression vectors pCK, which drives a high level of gene expression in the skeletal muscles of mice. In this study, we investigated the pharmacokinetics and biodistribution of pCK-VEGF expressing human VEGF165 after intravenous or intramuscular administration. The quantity of pCK-VEGF in the tissues of mice was measured by the PCR method which has a detection limit of approximately 1 pg of the exogenously added plasmid. In the case of intravenous administration, the half life of the pCK-VEGF plasmid in the bloodstream was 1.68 min. After intra-muscular administration, the half life of pCK-VEGF plasmid in the bloodstream was 6.78 min. At 90 min post-administration, 30% of the injected pCK-VEGF was found at the site of injection, where it persisted for up to 8 hours. Less than 1.6% of the injected pCK-VEGF plasmid DNA was detected in highly vascularized tissues such as the lung, kidney; and liver at 90 min post-administration, but the plasmid was undetectable at later time points. These results suggested that intramuscularly administrated pCK-VEGF persisted for longer periods of time in muscles than in other tissues and that direct intra-muscular injection of pCK-VEGF might be useful for local therapeutic angiogenesis.