Terminalia chebula pharmaceuticals were extracted by using the supercritical fluid extraction (SFE) technique. Under the optimal conditions of 184 [Formula: see text]L modifier volume, 46 min dynamic extraction time, and 316 atm fluid pressure, the extraction procedure was optimized by central composite design. A modified rapid expansion of supercritical solution (RESS) technique, named expansion of the supercritical solution (ESS) was used to create the extracted pharmaceutical nanoparticles (NPs). In ESS, supercritical carbon dioxide (SC-CO[Formula: see text] was saturated with the extracts at high-pressure. Next, a pressure drop reduced the SC-CO2 solubility power in a way the extracts started to precipitate. In contrast to RESS, the pressure was permanently conserved above the critical pressure before and after depressurization. Therefore, the expansion process was gentle, which led to obtaining small and uniform particles. In the NP production process, the most adequate parameters were 360[Formula: see text]atm premier pressure, 120[Formula: see text]atm subsequent pressure, 25[Formula: see text]min equilibrium time, 30[Formula: see text]min sedimentation time, and [Formula: see text]C temperature. The average size of precipitated NPs was 41[Formula: see text]nm according to the results of field emission scanning electron microscopy analysis. The liquid chromatography-mass spectrometry evaluation demonstrated the presence of chebulinic and chebulagic acids in the extracted sample.