Abstract： Objective To establish the high-performance liquid chromatography(HPLC)method for measuring concentrations of methotrexate(MTX)in rat lung and some other tissues through internal iliac artery infusion.Methods Fifly female Sprague-Dawley rats were included in this study.The rats were randomly assigned to two groups.Methotrexate was injected to group one through internal iliac artery,and was injected to group two through femoral vein.Blood and tissues were collected in each group at 15,30,60.90 and 120 minutes for detection of the drug concentrations with HPLC.Results The area under the concentration time curve(AUC)in rat lung,ovary and uterus in the artery group were separately(3.77±0.28),(4.40±0.40),(9.97±0.89)μg·h-1·g-1,which were significantly different from those of the vein group[(2.31±0.25),(3.91±0.19),(7.65±1.54)μg·h-1·g-1;P<0.05].The AUC in the rat plasma,heart,kidney,liver and spleen in the artery group were separately(6.13±0.53),(1.90 ±0.11),(5.32±0.89),(14.16±1.96),(0.76±0.20)μg·h-1·g-1.There were no significant differences from the vein group[(5.79±0.71),(1.64±0.29),(5.15±1.69),(14.29 ±3.47),(0.76±0.13)μg·h-1·g-1;P>0.05].Conclusions Through internal iliac artery infusion,there are higher drug concentrations in lung.uterus and ovarian compared to venous injection.The internal-arterial chemotherapy may be used to treat pulmonary metastasis of gynecological tumor.