The objective of this work was to synthesize magnetic matrices for immobilization of Burkholderia cepacia lipase to be used in the synthesis of alkyl esters.Two methods for the synthesis of the magnetic composites dispersed in silica matrices were tested: a) matrix polysiloxane-polyvinyl alcohol (SiO 2 -PVA) coating with Fe 3 O 4 and γFe 2 O 3 and b) matrix polysiloxane-polyvinyl alcohol (SiO 2 -PVA) synthesized with incorporation of Fe 3 O 4 and γFe 2 O 3. The matrix polysiloxane-polyvinyl alcohol (SiO 2 -PVA) and the composite Fe 3 O 4 and γFe 2 O 3 particles were used as controls.The morphological and textural characteristics of the magnetic and nonmagnetic matrices were determined by analysis of pore size (BET), scanning electron microscopy (MEV), X-ray diffraction and infrared spectroscopy (IV).The magnitete (Fe 3 O 4 ) and maghmitite (γFe 2 O 3 ) particles showed super paramagnetic behavior.The lipase B. cepacia was immobilized in the matrices (magnetized and nonmagnetized) by physical adsorption and covalent attachment and the similar immobilization yields obtained suggest that the iron particles did not affect the enzymesupport interaction.However, the determined kinetic parameters (K m and V max ) indicated that the lipase immobilized in both magnetized SiO 2 -PVA matrices had lower affinity for the substrate.The K m and V max values determined for free lipase (K m = 400 ± 32 mM and V max =16019 ± 749 Ug -1 ), showed that independely of the immobilization support the affinity of the enzyme for the substrate was reduced by 50%.The immobilized derivatives prepared by covalent attachment were used to mediate the transesterification reactions of coconut oil by ethanolysis route.All immobilized derivatives were efficient in the ethanolysis of coconut oil attaining total conversion to ethyl esters in 72 hours, with the exception of the immobilized lipase on Fe 3 O 4 and γFe 2 O 3 particles, which provided total conversion in 96 h, probably due to the negative influence of the iron particles on the enzyme.The purified product samples (biodiesel) were essentially odorless and translucent appearance.The purity of the ethyl esters was high.In addition, other properties such as density (873-876 kg m -3 ) and viscosity (3.76-3.93mm 2 s -1 ) meet the specifications required by the National Petroleum Agency (ANP) to be used as a biofuel.