Abstract: The correlation between the uptake of ~(99)Tc~m-MIBI and the expression of P-glycoprotein (Pgp) in patients with lung malignant tumor is explored by γ-detecting probe (GDP) intraoperatively. The results show that the Pgp expression of 5 patients with T/NT≤2 is much higher than that of the other 22 patients with T/NT>2. The higher the Pgp expression in lung malignant tumor cells, the lower the uptake of ~(99)Tc~m-MIBI is. It indicates that as a major factor of multidrug resistance, Pgp correlates with the uptake of ~(99)Tc~m-MIBI negatively in lung malignant tumors.