Background: We have reported a strong association between “triple-negative” breast cancer (TNBC) [estrogen receptor (ER) and progesterone receptor (PR) negative, HER2 negative] and the risk of having BRCA1 mutations in a meta-analysis. We hereby present a systematic review of a larger pool of specific data investigating the overall prevalence of BRCA1 mutations in women with TNBC. Methods: A Medline search combining the MeSH terms “BRCA” and “triple” and “negative” yielded 37 articles. A similar search in ASCO abstracts yielded 18 relevant articles. Prevalence in each study population as well as the overall prevalence was calculated. Results: 13 eligible studies (from year 2006 to 2011) including 1075 women with TNBC were identified. Out of 13, 1 study each was carried out on Ashkenazi Jewish and Hong Kong Chinese women respectively. Overall prevalence of BRCA1 mutations in women with TNBC is 20.93% (225 out of 1075) (range = 4.8%–43%). Ashkenazi Jewish women with TNBC have a higher-than-average prevalence of BRCA1 mutations (29.2%) although it is lower than the prevalence rates of some study populations. A remarkably low prevalence rate of BRCA1 mutations (4.8%) is found in Chinese women with TNBC. Conclusions: In view of the overall high prevalence rate of BRCA1 mutations (20.93%) in women with TNBC, genetic testing should be discussed with patients with TNBC. Further studies are suggested to evaluate the molecular basis of interestingly low BRCA1 prevalence (4.8%) in Chinese patients with TNBC.