<p>Subcritical CO₂ extraction (SBE-CO₂) is a new technology that utilizes CO₂ at high pressure and medium to high temperatures to recover bioactive compounds. Tiger nuts are rich in oil, starch, carbohydrates, and other natural substances and have a wide range of applications. In order to further investigate the value of tiger nut, the present study was carried out using one-factor experiment and response surface methodology (RSM) on SBE-CO₂ tiger nut and the extracted tiger nut oil was analyzed for fatty acids. Based on the results of the single-factor experiments, a Box-Behnken experimental design was used to study the extraction and separation process, focusing on variables such as extraction pressure, extraction time, and CO₂ circulation pump motor frequency (reflecting CO₂ flow rate). Fatty acid analysis of tiger nut oil was carried out using gas chromatography-mass spectrometry (GC–MS). Tiger nut oil contains a variety of fatty acid compounds, mainly including oleic, linoleic, and palmitic acids. In addition, in order to examine the energy demand and exergy loss in the subcritical CO₂ extraction cycle, the SUBCE-CO₂ buckling normal gas state separation process was simulated by Aspen Plus software, and the blocks of the subcritical CO₂ system were also analyzed by exergy. It was found that the potential for improvement of the throttle valve in the SBE-CO₂ system is minimal, although it has the highest exergy loss; the cooling unit HX2 has the highest energy demand. The exergy efficiency of the SBE-CO₂ system decreases slowly with increasing extraction pressure, while the energy consumption and exergy losses gradually increase.</p>