Abstract: Abstract：Objective To investigate the expressions of MDM2 and PTEN in bile duct carcinoma(BDC), and to evaluate their possible relationship and clinical signifi cance. Methods The protein levels of MDM2 and PTEN were examined by Elivision immunohistochemistry in 42 samples of BDC tissues and 22 samples of adjacent hepatic tissues. Results The expression rate of MDM2 in BDC tissues was 38.1%, signifi cantly higher than that in adjacent hepatic tissues (P<0.05). Patients with low differentiation or lymph node metastasis had a higher tendency to express MDM2 in BDC tissues (P<0.05). The expression rate of PTEN was 31.0% in BDC tissues, signifi cantly lower than that in adjacent hepatic tissues (χ2=10.168, P<0.05). For the PTEN expressions in BDC tissues, no statistical signifi cance was found in clinicopathological parameters, such as tumor size, differentiation, TNM stage or lymphnode metastasis (P>0.05). The expression of MDM2 was negatively correlated with that of PTEN in BDC tissues (rs=-0.313,P<0.05). Conclusion The expression of MDM2 may be associated with the progression of BDC. It may serve as an index for prognosis of BDC.