Background No reliable nomogram has been developed until date for predicting the survival in patients with unresectable pancreatic cancer undergoing treatment with gemcitabine plus nab-paclitaxel (GnP) or FOLFIRINOX (FFX).Methods This analysis was conducted using clinical data of patients with unresectable pancreatic cancer undergoing GnP or FFX treatment obtained from a multicenter study (NAPOLEON study). A Cox proportional hazards model was used to identify the independent prognostic factors. A nomogram to predict 6-, 12-, and 18-month survival probabilities was generated, validated by using the concordance index (C-index), and calibrated by the bootstrapping method. And then, we attempted risk stratification for survival by classifying the patients according to the sum of the scores on the nomogram (total nomogram points; TNP).Results A total of 318 patients were enrolled. A prognostic nomogram was generated using data on the Eastern Cooperative Oncology Group performance status, liver metastasis, serum LDH, serum CRP, and serum CA19-9. The C-indexes of the nomogram were 0.77, 0.72 and 0.70 for 6-, 12-, and 18-month survival, respectively. The calibration plot showed optimal agreement at all points. Risk stratification based on tertiles of the TNP yielded clear separations of the survival curves. The median survival times in the low-, moderate-, and high-risk groups were 15.8, 12.8 and 7.8 months (P<0.05), respectively.Conclusions: Our nomogram is a convenient and inexpensive tool to accurately predict survival in patients with unresectable pancreatic cancer undergoing treatment with GnP or FFX, and will help clinicians in selecting appropriate therapeutic strategies for individualized management.