Background/Aim: The performance of the circulating tumor markers carbohydrate antigen 19-9 (CA19-9), matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) were evaluated separately and in combination for their potential value in detecting pancreatic ductal adenocarcinoma. PATIENTS AND METHODS: The patients had symptoms of pancreatic cancer. The discriminative strength of MMP-9 and TIMP-1 were compared to that of CA19-9 using receiver operating characteristics curves, area under the curves (AUC), specificity and sensitivity. RESULTS: The sensitivities of MMP-9, TIMP-1 and CA19-9 in detecting pancreatic ductal adenocarcinoma were 58.82%, 47.1% and 86%, respectively, with specificities of 34.6%, 69.2% and 73%. The AUCs of MMP-9, TIMP-1 and CA19-9 were 0.50, 0.64 and 0.84, respectively. Combining the three markers did not significantly improve detection of pancreatic ductal adenocarcinoma compared to CA19-9 used alone. CONCLUSION: Circulating MMP-9 and TIMP-1 were inferior to CA19-9 as markers for detecting pancreatic ductal adenocarcinoma and did not improve the diagnostic accuracy when combined with CA19-9.