In order to study the expression of transformation suppressor gene RECK and MMP-9 in hilar cholangiocarcinomas and its clinical significance, and explore the roles of RECK gene in metastasis and invasion of hilar cholangiocarcinoma, the expression levels of RECK, and MMP-9 mRNA were detected by using reverse transcription-polymerase reaction in 42 paraffin-embedded samples of hilar cholangiocarcinomas and 10 samples of benign bile duct diseases. The results showed that in hilar cholangiocarcinoma tissues, the expression of RECK gene was 0.235 +/- 0.062, significantly lower than in normal bile duct tissues (0.533 +/- 0.024, P < 0.05). In hilar cholangiocarcinoma tissues, the expression of MMP-9 (0.528 +/- 0.039) was significantly higher than in the normal tissues (0.311 +/- 0.032, P < 0.05). The expression of RECK gene was closely related to the intrahepatic and surrounding organs invasion (P < 0.05). It was concluded that RECK gene could inhibit the expression of MMP-9 in hilar cholangiocarcinomas and closely correlated with the biological behaviors. The abnormal expression of RECK gene might be one of the molecular mechanisms of hilar cholangiocarcinoma metastasis.