The purpose of this work was to establish the best particle size for recovering high yields of total phenolic compounds (TPC), total anthocyanin compounds(TAC) and total flavonoid compounds (TFC) from roselle (Hibiscus sabdariffa) by applying supercritical carbon dioxide (ScCO2). The extraction rate, diffusivity and solubility of yield in ScCO2 were also studied and calculated utilizing models. Pressure (10 and 30 MPa), temperature (40 and 60 °C), and particle size (250 µm