In the current research, an ultrasound-assisted extraction (UAE) procedure was established for the protein extracted employing a reverse micelles system (RMS) from the by-product of the hazelnut oil industry. The optimum extraction circumstances in the UAE were identified as a dioctyl sodium sulfosuccinate (AOT) an amount of 0.05 g/mL, a water content of 25.2 (W0), a 0.02 g/mL solid-to-liquid ratio, ultrasound time of 17.52 min, ultrasound cycle 1, and ultrasound power 80% using the response surface approach. Under ideal circumstances, the maximum yield was recorded as 44.84 mg BSA/g of hazelnut meal protein (HMP) for RMS, it had a higher yield obtained by alkaline solution (AS). α-helix, β-turn, and β-sheet structures of HMP increased while the random coil decreased as evidenced by FTIR and SEM images proving that the cell walls were destructed and had more cracks in RMS. Overall, the findings indicated that UAE combined with RMS might be an effective approach for extracting protein from HMP and is likely to lead to an alternative evaluation possibility of an industrial by-product.