Candida rugosa lipase was immobilized on poly(N-methylolacrylamide) by physical adsorption. The biocatalyst performance (immobilized lipase) was evaluated in both aqueous (hydrolysis) and organic (butyl butyrate synthesis) media. In the first case, a comparative study between free and immobilized derivatives was provided in terms of pH, temperature and thermal stability following the olive oil hydrolysis, establishing new optimum values. In the second case, the influence of temperature, biocatalyst concentration and acid/alcohol molar ratio was simultaneously studied according to a 2(3) full experimental design. The highest molar conversion (96 %), volumetric productivity (1.73 g L-1 h(-1)) and specific esterification activity (1.00 mu M mg(-1) min(-1)) were obtained when working at the lowest level of temperature and butyric acid in excess. Under these conditions, repeated batch use of the immobilized enzyme was performed and half-life time (t(1/2)) was found to be 145 h.