This study was designed to develop and validate a nomogram for predicting intolerable early enteral nutrition (EEN) following definitive surgery (DS) for small intestinal fistula. A total of 377 patients, recruited from January 2016 to September 2023, was randomly allocated into development (n=251) and validation (n=126) groups in a 2:1 ratio. Risk factors were identified using the nomogram. Its performance was assessed based on calibration, discrimination, and clinical utility, with validation confirming its effectiveness. Of the 377 patients, 87 (23.1%) were intolerant to EEN, including 59 (23.1%) in the development cohort and 28 (22.1%) in the validation cohort (P=0.84). Four factors were identified as predictive of intolerable EEN: severe abdominal adhesion, deciliter of blood loss during DS, human serum albumin (Alb) input >40g during and within 48 hours post-DS, and the visceral fat area (VFA)/total abdominal muscle area index (TAMAI) ratio. The model demonstrated excellent discrimination, with a C-index of 0.79 (95% CI, 0.74-0.87, including internal validation) and robust calibration. In the validation cohort, the nomogram showed strong discrimination (C-index=0.77; 95% CI, 0.64-0.87) and solid calibration. Decision curve analysis affirmed the nomogram's clinical utility. This research introduces a nomogram that enables the individualized prediction of intolerable EEN following DS for small intestinal fistula, demonstrating a possible clinical utility.