Reverse micellar systems of nonionic surfactant Span 80/isooctane/n-hexane is used for the extraction of pectinesterase from crude aqueous extract of lemon peel waste. The effect of extraction process parameters on the extraction efficiency and activity recovery were studied in detail for the lemon peel extract. The optimum NaCl concentration (0.2 mol/L), Span 80 concentration (0.3 mol/L), the extraction phase pH (7.0), the temperature (60 degrees C), and oscillation time (30 min) were found out and the optimized conditions for the extraction from lemon peel waste resulted in back extraction efficiencies of 52.4%. A fairly good activity recovery (83.7%) of pectinesterase is obtained under these conditions.