The lignans phyllanthin and niranthin were extracted from Phyllanthus amarus using supercritical CO2 as solvent (SFE1) at different pressures (10, 20, 30 MPa) and temperatures (30, 40, 50 degrees C). The addition of 10% (w/w) of cosolvent (SFE2) was investigated at the same SFE1 conditions. Economic evaluation was performed for both processes. Temperature and pressure have no significant effects on the lignan yield of SFE2 with ethanol:water 50:50 v/v. The use of cosolvent increased the lignan recovery MS, but decreased the selectivity of the process. The SFE2 extracts showed lignan concentrations between 2.5% and 4.0%, whereas in SFE1 the lignan concentration of the extracts varied between 25% (60 degrees C/30 MPa) and 35% (40 degrees C/10-MPa). SFE2 (40 degrees C/10 MPa) presented the lowest cost of manufacturing. However, the SFE1 extract (40 degrees C/20 MPa) is ten times purer, which is a remarkable advantage given that the subsequent purification processes are expensive.