Abstract: Objective To analyze the correlation between molecular subtypes and axillary lymph node（ALN） metastasis of breast cancerMethods A total of 773 patients with breast cancer at 1-3 stages admitted to Chinese PLA General Hospital from January 2000 to December 2009 were enrolled in this study.Breast cancer were divided into luminal A molecular subtype（ER+ and/or PR+,HER2-）,luminal B1 molecular subtype（ER+,PR+,HER²⁺）,luminal B2 molecular subtype（ER+ or PR+,HER-²⁺）,HER-2 molecular subtype（ER-,PR-,HER-²⁺） and basal molecular subtype（ER-,PR-,HER-2-） according to the expression of ER,PR and HER-2.Differences in positive axillary ALN metastasis of 5 molecular subtypes of breast caner were analyzed.Logistic regression analysis was performed for the factors influencing axillary ALN metastasis of breast cancerResults The axillary ALN metastasis rate was the highest for luminal B1 molecular subtype of breast cancer followed by HER-2 molecular subtype,luminal B2 molecular subtype,basal molecular subtype,and luminal A molecular subtype.A significant difference was observed in axillary ALN metastasis rate for different molecular subtypes of breast cancer（P＜0.05）.Logistic regression analysis showed that luminal B1 molecular subtype,luminal A molecular subtype,age of patients,tumor size,histological grade,mucoid adenocarcinoma,and early invasive carcinoma are the independent factors for axillary ALN metastasis of breast cancerConclusion The axillary ALN metastasis rate is high for luminal B1 molecular subtype,HER-2 molecular subtype,and Luminal B2 molecular subtype of breast cancer expressing HER-2.The molecular subtypes of breast cancer are related with the axillary ALN metastasis of breast cancer.