Autologous fat transplantation is often used in aesthetic plastic surgery, and is recently becoming increasingly popular in the reconstruction of soft tissue defects following oncological surgery. A still not standardized technique of fat transplantation for breast cancer reconstruction is rapidly getting popular. The procedure is not a passive volume replacement, but transplantation of biologically active tissue bearing endocrine, paracrine, exocrine functions and containing fat-derived stem cells, which in the tumorous environment raises many questions in relation to the oncological safety and diagnostic follow-up. Although long-term results based on prospective, randomized studies are not yet available, published clinical experience is promising and reveals an effective and surgically safe procedure if used with appropriate indications and techniques. The authors conducted a broad review of the literature, presenting indications, technique, molecular interactions, and potential risks of the clinical results of autologous fat transplantation in the breast cancer reconstructive surgery. The authors initiated that breast and plastic surgeons should promote adequate long term follow-up of breast cancer patients who underwent breast reconstruction with autologous fat transplantation by the establishment of national registries. Orv. Hetil., 2012, 153, 1816–1831.