--- - |2- In our study, human breast cancer biopsies were decellularized by the detergent technique with sodium lauryl ether sulfate (SLES) solution for the first time. Scaffolds seeded with MCF‐7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial‐to‐mesenchymal transition (EMT) process. When treated with 5‐fluorouracil (5‐Fu), the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. Abstract Breast cancer, with unsatisfactory survival rates, is the leading cause of cancer‐related death in women worldwide. Recent advances in the genetic basis of breast cancer have benefitted the development of gene‐based medicines and therapies. Tissue engineering technologies, including tissue decellularizations and reconstructions, are potential therapeutic alternatives for cancer research and tissue regeneration. In our study, human breast cancer biopsies were decellularized by a detergent technique, with sodium lauryl ether sulfate (SLES) solution, for the first time. And the decellularization process was optimized to maximally maintain tissue microarchitectures and extracellular matrix (ECM) components with minimal DNA compounds preserved. Histology analysis and DNA quantification results confirmed the decellularization effect with maximal genetic compounds removal. Quantification, immunofluorescence, and histology analyses demonstrated better preservation of ECM components in 0.5% SLES‐treated scaffolds. Scaffolds seeded with MCF‐7 cells demonstrated the process of cell recellularization in vitro, with increased cell migration, proliferation, and epithelial‐to‐mesenchymal transition (EMT) process. When treated with 5‐fluorouracil, the expressions of stem cell markers, including Oct4, Sox2, and CD49F, were maximally maintained in the recellularized scaffold with decreased apoptosis rates compared with monolayer cells. These results showed that the decellularized breast scaffold model with SLES treatments would help to simulate the pathogenesis of breast cancer in vitro. And we hope that this model could further accelerate the development of effective therapies for breast cancer and benefit drug screenings. - 'Journal of Cellular Physiology, EarlyView. '