【Abstract】 Objective To explore the distribution of thymidylate synthase ( TYMS) gene in advanced triplenegative breast cancer (TNBC) patients and the relationship between the gene expression and the effect of chemotherapy. Methods 97 patients with advanced TNBC were treated with TAC, TP, or TX scheme, and each patient was detected TYMS gene mRNA expression with liquid chip technology, then analyzed the status of TYMS gene expression in TNBC, and the relationship between TYMS gene expression and chemotherapy curative effect. Results TYMS gene mRNA expression in TNBC had no obvious correlation with age, menstrual status, histological grade, transfer parts, Ki67 and PS score, the P value was greater than 005. TYMS gene expression was related with the effect of fluoropyimidine. Lower expression had a good curative effect. The difference was statistically significant. Conclusion TYMS gene might be a predicted genes of chemotherapy curative effect in TNBC. Tt was deserved further research.