Background <p>The neutrophil to high-density lipoprotein cholesterol ratio (NHR) predicts disease severity in biliary pancreatitis, yet its prognostic role in hypertriglyceridemic acute pancreatitis (HTG-AP) remains unclear.</p> Methods <p>This study enrolled 421 eligible patients diagnosed with HTG-AP. Baseline comparisons were made using the Mann-Whitney U Test and Chi-Square Test. Logistic regression analysis was employed to identify risk factors for HTG-AP severity. The predictive value of NHR was assessed using the Integrated Discrimination Improvement (IDI) and the Net Reclassification Index (NRI). Restricted cubic splines (RCS) were used to evaluate nonlinear associations. Subgroup analyses further explored the correlation between NHR and HTG-AP severity.</p> Results <p>Patients with moderate/severe HTG-AP exhibited significantly higher NHR levels than those with mild disease (<i>p</i> &lt; 0.001). Elevated NHR correlated with prolonged hospitalization (<i>p</i> = 0.016), higher rates of acute peripancreatic fluid collection (APFC) (<i>p</i> &lt; 0.001) and acute necrotic collection (ANC) (<i>p</i> = 0.008). NHR was an independent risk factor for moderate/severe HTG-AP (<i>p</i> &lt; 0.001) and improved the predictive accuracy of the risk assessment model. NHR led to only a small improvement in AUC within the model, which indicated some limitations in predicting HTG-AP severity. RCS analysis revealed a linear relationship between NHR and HTG-AP severity (p for non-linearity &gt; 0.05).</p> Conclusion <p>NHR is a simple, early biomarker for predicting HTG-AP severity, offering potential utility in guiding timely clinical interventions.</p>