Breast cancer is the most prevalent cancer worldwide. Many published articles have evaluated the association between the transforming growth factor beta 1 (TGFB1) T29C polymorphism and breast cancer risk. However, the results remain inconclusive. In order to derive a more precise estimation of the association, a meta-analysis was performed in this study. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the association. A total of 12 studies including 10,417 breast cancer cases and 11,455 controls were identified. Overall, no significant associations between the TGFB1 T29C polymorphism and breast cancer risk were found for CC versus TT (OR = 1.00, 95% CI = 0.92-1.09), TC versus TT (OR = 0.98, 95% CI = 0.93-1.05), CC/TC versus TT (OR = 0.99, 95% CI = 0.93-1.05), and CC versus TC/TT (OR = 1.00, 95% CI = 0.93-1.08). In the subgroup analysis by ethnicity, source of controls, and menopausal status, there was still no significant association detected in all genetic models. In conclusion, the present meta-analysis suggests that the TGFB1 T29C polymorphism is not a low-penetrant risk factor for developing breast cancer.