Aim: To develop a prognostic model to predict the overall survival of primary bladder neuroendocrine carcinoma (BNEC) patients. Methods: Using univariate and multivariate Cox regression analyses, a nomogram was constructed. Calibration curves, receiver operating characteristic curves and C-index were utilized to evaluate the performance. Results: The study enrolled 906 BNEC patients. The following variables were incorporated in the nomogram: age, marital status, Tumor node metastasis (TNM) stage, chemotherapy and surgery. The nomogram had a C-index of 0.702 in the training cohort and 0.724 in the validation cohort. Conclusion: Compared with the TNM staging system, the proposed nomogram exhibits superior prognostic discrimination and survival prediction.