Background/aims: The Triglyceride-Glucose (TyG) index, recognized as an indicator of insulin resistance and metabolic syndrome, has been correlated with various cancer risks, including that of breast cancer (BC). This systematic review and meta-analysis sought to investigate the relationship between the TyG index and the risk of developing BC, as well as its potential in distinguishing between malignant and benign breast conditions. Methods: An extensive search of the literature was conducted across databases such as PubMed, Scopus, Web of Science, and Google Scholar until July 2024. Observational studies reporting TyG index values alongside their correlation with BC were included. Results: A total of thirty studies, encompassing 2,058,536 participants, were analyzed. The findings revealed that a higher TyG index significantly correlated with increased BC risk (Effect Size [ES]: 1.65, 95% Confidence Interval [CI]: 1.15–2.36, p = 0.006). Individuals in the highest TyG index category had a 1.87-fold greater risk of BC compared to those in the lowest category (ES: 1.87, 95% CI: 1.45–2.41, p = 0.001). This association was notably stronger in Asian populations. Moreover, patients with malignant breast lesions showed elevated TyG index values in contrast to those with benign lesions ( p < 0.001). Conclusion: An elevated TyG index is significantly linked to a heightened risk of BC and may be useful for differentiating between benign and malignant breast lesions. Further exploration into the clinical applicability of the TyG index as a cost-effective screening tool is suggested.