Objective:To investigate the heterogeneity of chemosensitivity in breast carcinoma using adenosine triphosphate based tumour chemosensitivity assay(ATP-TCA) and the feasibility of individual chemotherapy. Methods:ATP-TCA was used to determine the effect of 6 single drugs in surgical specimens from 75 patients with breast carcinoma. And 60 patients with breast carcinoma were used as matched control group. Results:All above these specimens were detected successfully. The sensitivity of six drugs was 25.33% for THP,21.33% for E-ADM,20.00% for DTX,13.33% for MTX,12.00% for gemcitabine,6.67% for 5-Fu in these specimens respectively. There were the heterogeneity of the in vitro chemosensitivity in breast carcinoma and had statistical significance(P < 0.05). After three years followed up,the relapse rate of therapy group was lower than that of the matched control group with statistical significance(P < 0.05). Conclusion:The use of the ATP-TCA may provide a method of selecting appropriate anti-cancer drugs of breast carcinoma in chemotherapy of individualization.