Objective To explore the value of carcinoembryonic antigen ( CEA) and cancer antigen 153 ( CA153 ) in detecting tumor recurrences and to establish the optimal operating point of diagnosis of recurrences in HER-2 overexpressing breast cancer using ROC curves .Methods A total of 127 HER -2 overexpressing breast cancer patients was enrolled into this study and subdivided into two groups ,the recurrence group and the non-recurrence group .We created a ROC curve and found out the optimal operating point .Then we compared the advantage of detecting recurrences between optimal operating point in the ROC curve and the diagnostic point that we usually used .Results The recurrence groups showed significantly higher CEA and CA 153 levels than the non-recurrence groups(P<0.0001).The area under the curve(AUC)of the CEA and CA153 were 0.752 and 0.820 respectively and the optimal operating point were 3.5 ng/mL and 17.89 U/mL,respectively.The sensitivi-ties of the optimal operating point of CEA and CA 153 were 46.15%and 65.38%respectively,and the specifici-ties were 97.33%and 89.33%, respectively.Conclusion CEA and CA153 process medium value for detecting recurrences in HER-2 overexpressing breast cancer .