The main objective of this work was to investigate the high pressure phase behavior of the binary system CO2 + priprioca (Cyperus articulatus L) extract. The static synthetic method using a variable-volume view cell was employed for obtaining the experimental data. Data were collected in the overall composition range of 0.101-0.995 weight fraction CO2, from 313 K to 333 K at pressures up to 30 MPa. For these systems, the experimental data revealed liquid-vapor and liquid-liquid phase transitions. Thermodynamic modeling was performed using the Peng-Robinson equation of state with the classical quadratic mixing rules; satisfactory agreement was obtained between experimental and calculated values. (C) 2008 Elsevier B.V. All rights reserved.