OBJECTIVE Chylous ascites (CA) may be involved in the pathological process of severe acute pancreatitis (SAP), but the underlying mechanisms remain unknown. This study investigated the incidence of CA in patients with SAP and its relationship with enteral nutrition (EN). METHODS A retrospective review of 85 patients with SAP admitted to our hospital was performed. Patients starting EN within 72 hours after the onset of SAP were classified as the early EN (EEN) group, and others, as the later EN group. The incidences of CA and prognosis in the EEN and later EN groups were examined with nutrition preparation of polymeric formula or semielemental feed. RESULTS Thirteen (15.29%) of 85 patients were identified with CA. A higher incidence of CA was observed in EEN patients who received polymeric formula (9 of 33, P < 0.05). All patients with CA were successfully treated with a modified medium-chain triglyceride diet. Consequently, there were no differences in intensive care unit stay and in mortality rates in patients with or without CA. CONCLUSIONS There was a higher incidence of CA associated with early enteral feeding of polymeric formula in patients with SAP. Future studies are warranted to confirm our findings and evaluate better enteral feeding options to avoid CA.