Despite expression of oncogenic KRAS, premalignant pancreatic intraepithelial neoplasia 1 (PanIN1) lesions rarely become fully malignant pancreatic ductal adenocarcinoma (PDAC). The molecular mechanisms through which established risk factors, such as chronic pancreatitis, acinar cell damage, and/or defective autophagy increase the likelihood of PDAC development are poorly understood. We show that accumulation of the autophagy substrate p62/SQSTM1 in stressed KrasG12D acinar cells is associated with PDAC development and maintenance of malignancy in human cells and mice. p62 accumulation promotes neoplastic progression by controlling the NRF2-mediated induction of MDM2, which acts through p53-dependent and -independent mechanisms to abrogate checkpoints that prevent conversion of differentiated acinar cells to proliferative ductal progenitors. MDM2 targeting may be useful for preventing PDAC development in high-risk individuals. Display omitted •IKKα-deficiency-induced p62 accumulation drives PDAC progression•MDM2 links the autophagy substrate p62 to neoplastic progression in the pancreas•A p62-NRF2-MDM2 module acts via p53-dependent and -independent mechanisms•A p62-NRF2-MDM2 module converts acinar cells into progenitor-like cells Todoric et al. demonstrate that pancreatitis-induced accumulation of the autophagy substrate p62/SQSTM1 in the context of oncogenic KRAS promotes progression to pancreatic ductal adenocarcinoma. This p62 function relies on NRF2-driven induction of MDM2 and both p53 dependent and independent activity of MDM2.