Lipases catalyze the hydrolysis of triglycerides at the oil-water interface. This reaction is reversible and the enzyme also catalyzes the synthesis of esters and transesterification in microaqueous conditions. Lipases are ubiquitous enzymes, and with the rapid development of enzyme technology, many new potential biotechnological applications for lipases have been identified in the areas of detergents, oilchemistry, food processing, organic synthesis, paper manufacturing, biosurfactant synthesis, cosmetics and pharmaceutical industries. The aim of the present investigation was to purify and perform a preliminary characterization of the lipase from Pachira aquatica. The enzyme was purified to homogeneity by ultrafiltration, followed by modified polyacrylamide gel electrophoresis (PAGE). The characterization procedure was done by assaying enzyme activity with nitrophenyl-esters as substrates. This purification protocol rendered a lipase dimer having an estimated Mw of 90 KDa by SDS-PAGE. The enzyme activity was higher in the presence of CaCl₂ and MgCl₂, but inhibited by CoCl₂, MnCl₂, AlCl NaCl and KCl. The presence of oxidizing, reducing and chelating compounds reduced enzyme activity. K_m  and V_max were calculated with p-nitrophenyl acetate as a substrate:  0.94 mM  and 1.9mM/min, respectively.  In terms of substrate specificity, the enzyme was more active on p-nitrophenyl acetate than using longer fatty acids. The effect of salts (LiCl, NaCl and KCl) on lipase activity was also studied, decreasing with the increasing salt content. Hydrolitic activity showed different effects depending on the salt. The enzyme was able to hydrolyze both soluble and insoluble emulsified substrates and was classified as a lipase, expressing some esterase activity as well. Financial Support CAPES (PPP), FAPESP (05/03157-1) (FDAF), FAPESP (03/00085-4) and CNPq (GOBR).