OBJECTIVES: To investigate the association between lipid ratios and survival outcomes in patients with locally advanced breast cancer (LABC) undergoing neoadjuvant chemotherapy. METHOD: This retrospective study included patients with LABC receiving neoadjuvant chemotherapy. Serum lipid levels were prospectively measured at baseline. Associations of triglyceride to total cholesterol (TG/TC), triglyceride to high-density lipoprotein (TG/HDL) and triglyceride to low-density lipoprotein (TG/LDL) ratios with prognosis were evaluated. RESULTS: < 0.001), and the TG/LDL ratio demonstrated the best predictive efficacy (TG/TC vs. TG/HDL vs. TG/LDL, 1-year AUC: 0.724 vs. 0.676 vs. 0.846, 2-year AUC: 0.653 vs. 0.638 vs. 0.708). CONCLUSION: Baseline serum TG/TC, TG/HDL and TG/LDL ratios were independent prognostic factors in patients with LABC undergoing neoadjuvant therapy. However, their utility in predicting the early DFS events warrants further investigation. CLINICAL TRIAL REGISTRATION: NCT05621564.