Grape Pomace Flour (GPF) is a by-product of the wine industry that is currently un-derutilized. This research aimed to determine the functional and nutritional properties of GPF from Coahuila, Mexico. The experimental strategy included the evaluation of the color parameters in GPF with different particle sizes; subsequently, the determination nutritional parameters (moisture, ash, minerals, fat, protein, and carbohydrates) were determined and finally the func-tional parameters: water solubility index (WSI), swelling power (SP), water absorption index (WAI) and oil absorption index (OAI) in GPF, as well as the determination and identification of bioactive compounds by HPLC-MS. The results showed better color characteristics in particle size less than 180 µm. GPF is a good source of minerals such as potassium, magnesium, and calcium, highlighting that the magnesium content is higher than in other grape pomace flours. The results of the functional properties showed that GPF presented higher values of WAI (2.64 ± 0.06 g/g), WSI (5.75 ± 0.61 %), and SP (2.80 ± 0.05mL/g) than commercial flours. Finally, GPF presented a high content of phenolic compounds; the HPLC analysis identified important bioactive phenolic compounds. In conclusion, GPF has exceptional functional and nutritional properties, surpassing many conventional flours and aligning with non-conventional ones. GPF's natural color enhances product appeal, making it a versatile, nutrient-rich ingredient that improves food quality.