Objective To study the significance of c-met mRNA in axillary drainage after operations for breast cancer. Methods RT-PCR assay was used to examine c-met mRNA in axillary drainage after operations in 52 cases of breast cancer. The relationships between the expression of c-met and the tumor size, metastatic lymph nodes， the expressions of estrogen receptor (ER), progesterone receptor (PR) and c-erbB-2 were analyzed, respectively. In addition, the effect of douching operative field with 5-FU and distilled water on the expression of c-met mRNA was also analyzed. Results ①The proto-oncogene c-met mRNA could be detected in axillary drainage after operations for breast cancer by RT-PCR, and its positive rate was higher than that in routine pathological detection for micrometastasis in the axillary lymph nodes (P＜0.05). ②The expression of c-met mRNA was correlated with both the metastatic lymph nodes and tumor size. ③There was no significant relationship between the expression of c-met mRNA and the expressions of ER, PR and c-erbB-2. ④Dounching operative field with 5-FU and distilled water could decrease the expression of c-met mRNA.Conclusion The proto-oncogene c-met mRNA may be an ideal and specific marker for dectecting micrometastasis of breast cancer. In addition, it also suggests that the examination of c-met mRNA in the axillary drainage by RT-PCR assay could detect the micrometastasis in axillary lymph nodes much easier and more accurately than routine pathological method.