To study the features of tumor microenvironment (TME) of BM brain metastasis, a proteomic approach has been performed in a preclinical BM model with the human lung adenocarcinoma-derived H2030-BrM3 cells implanted into the cortex and striatum of nude rats. Proteomic analyzes were performed 24 days after tumor cell inoculation. Here, we provided protein expression changes in BM compared to healthy brain tissue with rat analyzes. In total, 8420 proteins were quantified from the 8 samples analyzed.