<p>Corn germ, an underutilized byproduct of the corn milling industry, is rich in nutritional components but has a limited shelf life. Multigrain flour, a blend of two or more grains ground into fine flour, was the focus of this study. Producing multigrain flour by combining wheat, barley, oats and corn flour and then incorporating it with microwave-treated corn germ moiety at varying concentrations of 3–15% (T₀-T₅). The study’s investigation into the effect of MTGM incorporation on the nutritional profile of the flour revealed significant enhancements. Findings showed that the flour exhibited an increased moisture content of 14.32%, crude protein of 15.77%, crude fat of 8.54%, crude fiber of 4.74%, and crude ash of 3.78% compared to the control sample, providing valuable insights into the enhanced nutritional benefits of the flour. Conversely, the nitrogen-free extract (NFE) was found to be 52.85%, indicating a decrease compared to the control. Notably, the addition of microwave-treated corn germ to the multigrain flour led to a significant improvement in the antioxidant profile (TPC, TFC, and DPPH), reaching 84.4%, 84.5%, and 60.66%, respectively. The Fourier-transform infrared spectroscopy (FTIR) result revealed a diverse range of functional groups, and gas chromatography analysis detected five fatty acids in the developed flour. Despite a reduction in gluten content (29.7%) and an increase in free fatty acid content (1.7%) with higher concentrations of treated corn germ, the overall findings suggest that microwave-treated corn germ could be a valuable supplementary ingredient for flour.</p>