Objective: To observe the abnormal DNA methylation inhibits the miRNA expression in pancreatic cancer cell line, and DNA methyltransferase inhibitor on the miR-615-5p of the methylation status and expression in the pancreatic cancer cell line PANC-1. Methods: Methylation microarray was used to screen in pancreatic cancer cell line PANC-1 in the abnormal methylation of miRNA. PANC-1 cells were treated with demethylating agent 5-aza-2-adeoxycytidine (5-aza-dC) in vitro, Methylation specific polymerase chain reaction (methyla-tion- specific PCR, MSP) combination of bisulfite modified DNA sequencing method (bisulfite-sequencing PCR, BSP) were used to detect miR-615-5p methylation changes before and after treatment. The changes of miR-615-5p expression was detected by quantitative RT-PCR before and after treatment. Results: Methylation was significantly higher in pancreatic cancer cell line PANC-1 than in normal tissue by MSP and BSP methods. miR-615-5p reduction in methylation was associated with the expression reactivation in the pancreatic cancer cells PANC-1 treated with demethylation agent 5-aza-dC. Conclusion: This study demonstrates that aberrant DNA methylation of the miR-615-5p CpG island is closely linked to their inappropriate silencing in pancreatic cancer cell line PANC-1.