Abstract： Objective To investigate the effect of CEF-T six-cycle chemotherapy on blood lipid and related factors in patients with invasive breast cancer. Methods A retrospective study was performed on 211 cases of patients with invasive breast cancer who were admitted from January 2014 to March 2018. All patients were treated with modified mastectomy or breast-conserving radical mastectomy,and all patients were treated with cef-t six cycles of adjuvant chemotherapy. The treatment regimen was cyclophosphamide+ surfactant + fluorouracil,and the sequential treatment was docetaxel. Blood lipids were measured before and 1 d before each cycle of chemotherapy,and multiple factors were analyzed for age,body mass index, menopause,tumor stage,and blood lipid level. Results After adjuvant chemotherapy,57 patients showed increased triglyceride,and 6 patients were finally diagnosed as hypertriglyceridemia. The number of patients with increased triglyceride level in the third cycle increased significantly,and the difference was statistically significant (P<0. 05). There were 51 patients with elevated cholesterol,and 5 patients were finally diag&nbsp;nosed withhypercholesterolemia. Compared with cycle 3,the number of patients with elevated total cholester-ol level in cycle 4 increased significantly,with statistically significant differences (P<0. 05). Age,body mass index,and menopause may be risk factors for elevated triglycerides and cholesterol during adjuvant chemotherapy. Conclusion The effect of CEF-T six-cycle adjuvant chemotherapy on lipid metabolism in vivo is positive. Age,body mass index,menopause were risk factors for elevated triglycerides and cholesterol during adjuvant chemotherapy. Breast cancer patients with lipid metabolic disorder have poor prognosis and are prone to recurrence and metastasis. The abnormal blood lipid metabolism in the course of adjuvant chemotherapy can reduce the recurrence and metastasis of breast cancer.