Our results indicate that high expression of GATA3 is associated with an unfavorable prognosis and is a predictive factor associated with TTP in breast cancer patients (pooled HR = 0.671; 95% CI = 0.475–0.947; P = 0.023) but is not significantly associated with OS (pooled HR = 0.889; 95% CI = 0.789–1.001; P = 0.052). This evidence concerns the gene GATA3 and breast cancer.