In the last decades bioengineered tumor models has garnered great attention in order to supply the long lasting research tools to study better the dynamic mechanisms for driving cancer progression, invasion and metastasis. Cancer biology has been studied by mean of 2D cell cultures or xenograft animal models, however, these systems do not faithfully copycat the tumor microenvironment. 3D tumor model using biomaterials has come as cost-effective, easy to handle and able to mimic the complexity of the cancer microenvironment. In this work, a 3D breast cancer model based on freeze-dried silk fibroin scaffold (SF) has been initiated. SF from mulberry silkworm Bombyx mori is used dueto its good biocompatibility, elasticity, toughness, suitable mechanical properties and biodegradability with tunable degradation rates. Breast cancer cells and mammary fibroblast are seeded on natural derived biomaterial matrix to better mimic the tumor microenvironment and the crosstalk between cancer cells and stroma. Proliferation and morphology of the cells are evaluated in the monoculture and cocolture systems. The different expressions of some ECM markers are investigated to characterize the tumor microenvironment. This biomaterial based 3D breast micro-tumor model may be a tool to predict the effect of the drugs according to the genetic heterogeneity of breast cancer. The use of the bioengineered platform will shorten the evaluation time of a drug response and will offer a more realistic tool to study the mechanism of action of the drugs.