Abstract: S180 tumor-bearing mice were used to study the pharmacokinetics and biodistribution in lung, bone and tumor issues of vinorelbine-loaded liposome(L-NVB)and vinorelbine injection(NVB) in vivo. AUC _0-∞ and c_max of L-NVB higher than NVB, indicating its potential to improve theraputic effectiveness. While the decrease of CL_z and the increase of MRT of L-NVB revealed that the liposomes could prolong the resistance time in blood and increase the drug amount that diffused into tumor tissues. Although the elimination tendency in lung, bone and tumor was similar, L-NVB displayed significantly decreased bone accumulation(P< 0. 01)and significantly increased tumor accumulation(P< 0. 001)compared with common NVB. These results demonstrated L-NVB could accumulate in tumor tissue due to enhanced permeability and retention effect, which improved the tumor targeting capability and reduced the drug dosage in other tissue such as bone. L-NVB showed better clinical potential with reduced toxicity and improved theraputic effectiveness.