The long non-coding RNA CERS6 antisense RNA 1 (CERS6-AS1) has critical regulatory roles in breast cancer progression. Here, we determined CERS6-AS1 expression in pancreatic ductal adenocarcinoma (PDAC) and the roles of CERS6-AS1 in PDAC carcinogenesis. The mechanisms underlying the regulatory actions of CERS6-AS1 in PDAC cells were elucidated in detail. CERS6-AS1 expression was evidently increased in PDAC tissues and cell lines. Patients with PDAC having high CERS6-AS1 expression had shorter overall survival periods than those having low CERS6-AS1 expression. Functionally, the knockdown of CERS6-AS1 attenuated the proliferation, migration, and invasion and stimulated apoptosis of PDAC cells in vitro. Additionally, CERS6-AS1 depletion decreased PDAC tumor growth in vivo. Mechanistically, CERS6-AS1 could competitively bind to microRNA-15a-5p (miR-15a-5p) and effectively work as a molecular sponge in PDAC cells, resulting in the upregulation of fibroblast growth factor receptor 1 (FGFR1), a direct target of miR-15a-5p. Rescue experiments revealed that miR-15a-5p downregulation or FGFR1 restoration rescued the effects of CERS6-AS1 knockdown on the behaviors of PDAC cells. In conclusion, CERS6-AS1 promoted the oncogenicity of PDAC by serving as a competing endogenous RNA to sequester miR-15a-5p and increase FGFR1 expression, which highlights the potential of the CERS6-AS1/miR-15a-5p/FGFR1 pathway as an effective target for cancer therapy.