Objective:To explore the relationships between serum lipids, CA153 level and breast cancer incidence and clinicopathological features of patients.Methods:A total of 198 patients with breast cancer diagnosed and treated at Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School were enrolled as the case group, and 198 healthy women were selected with 1∶1 age pairing as controls. Five milliliters of fasting venous blood was collected to measure serum lipids levels in all subjects and CA153 levels in breast cancer patients. The difference of serum lipids levels between the two groups was compared. Logistic regression model was used to analyze the risk factors of breast cancer. For 165 breast cancer patients who did not receive neoadjuvant chemotherapy, independent sample t-test was used to compare serum lipids and CA153 levels in breast cancer patients with different pathological features, and Pearson correlation analysis was used to calculate the correlation between variables and CA153. Results:The triglyceride (TG) levels in the case group and the control group were (1.22±0.73) mmol/L and (1.06±0.52) mmol/L respectively, and the difference was statistically significant ( t=2.559, P=0.011); the total cholesterol (TC) levels were (4.47±0.86) mmol/L and (4.99±0.80) mmol/L respectively, and the difference was statistically significant ( t=-6.228, P<0.001); the high-density lipoprotein cholesterol (HDL-C) levels were (1.32±0.34) mmol/L and (1.53±0.38) mmol/L respectively, and the difference was statistically significant ( t=-5.913, P<0.001). Higher TC and HDL-C levels were independent protective factors for breast cancer ( OR=0.350, P<0.001; OR=0.531, P=0.013). The TC levels in lymph node positive and lymph node negative patients were (4.36±0.73) mmol/L and (4.67±0.83) mmol/L respectively, and the difference was statistically significant ( t=-2.518, P=0.013); low-density lipoprotein cholesterol (LDL-C) levels were (2.53±0.58) mmol/L and (2.77±0.70) mmol/L respectively, and the difference was statistically significant ( t=-2.312, P=0.022). The TC levels in patients with stage Ⅰ and stage Ⅱ/Ⅲ were (4.90±0.89) mmol/L and (4.46±0.76) mmol/L respectively, and the difference was statistically significant ( t=2.855, P=0.005); LDL-C levels were (2.95±0.71) mmol/L and (2.60±0.63) mmol/L respectively, and the difference was statistically significant ( t=2.705, P=0.008). The level of CA153 in triple-negative breast cancer patients [(14.94±7.45) U/ml] was significantly higher than that in non-triple-negative breast cancer patients [(11.96±5.96) U/ml], and the difference was statistically significant ( t=2.359, P=0.020). The level of CA153 was positively correlated with the level of TG ( r=0.167, P=0.032). Conclusion:Dyslipidemia is associated with an increased risk of breast cancer. The levels of serum lipids vary among patients with different lymph node status and tumor stages. CA153 level is positively correlated with TG level to some extent.