Chloride intracellular channel 1 (CLIC1), a newly discovered member of the chloride channel protein family, has been implicated in multiple human cancers. However, little is known with regard to its expression and biological functions in pancreatic cancer. In this study, we focused on the clinical significance and biological functions of CLIC1 in pancreatic cancer and found that this protein was overexpressed in pancreatic cancer tissues. Patients with CLIC1-positive tumours had worse overall survival than those with CLIC1-negative tumours. Furthermore, the treatment of pancreatic cancer cell lines with CLIC1-targeting siRNA oligonucleotides significantly reduced cell proliferation and diminished anchorage-independent growth on both soft agar and cell migration. These data indicate that CLIC1 acts as a putative oncogene in pancreatic cancer and may represent a novel diagnostic and therapeutic target for pancreatic cancer.