NOVELTY - Method (M1) for preparing lipase enzyme complex having magnetic response involves (a) obtaining lipase solution (A), (b) obtaining lipase solution (B), (c) mixing the obtained lipase solution (A), and lipase solution (B) to obtain mixed solution, (d) preparing sodium alginate solution, (e) mixing the mixed solution with sodium alginate solution, and (f) adding the resulting stirred solution drop wise into calcium chloride solution, hardening capsules, washing capsules with distilled water, and phosphate buffered saline for several times, and storing product.    USE - The method is useful for preparing lipase enzyme complex having magnetic response which is used for producing biodiesel (all claimed).    ADVANTAGE - The method enables to realize easy recovery and reuse of enzyme, and reduce loss of enzyme activity during reaction.    DETAILED DESCRIPTION - Method (M1) for preparing lipase enzyme complex having magnetic response involves (a) dispersing nano iron oxide nanoparticles, where the nanoparticle is modified at 1,3-position in 5-25 U/ml phosphate buffer solution having pH of 8 to obtain lipase solution (A), (b) dispersing iron oxide nanoparticles without modified position in 8.5-20 U/ml phosphate buffer solution to obtain lipase solution (B), (c) mixing the obtained lipase solution (A), and lipase solution (B) in volume ratio of 0.5-10:1 to obtain mixed solution, (d) preparing 3-6 %mass sodium alginate solution having pH of 8-10, (e) mixing the mixed solution obtained in the step (c) with sodium alginate solution in volume ratio of 2:1 and stirring the resulting solution for 0.5-2 hours, and (f) adding the resulting stirred solution drop wise into 1-5% calcium chloride solution to obtain microcapsule having diameter of 2-3 mm, filtering the resulting microcapsules, hardening the filtrate for 3-5 hours using 1 %mass glutaraldehyde solution, immobilizing the hardened capsules at 4 degrees C for 3-12 hours, washing the immobilized capsules with distilled water, and phosphate buffered saline for several times, and storing product at 4 degrees C. An INDEPENDENT CLAIM is included for method (M2) of preparing biodiesel, which involves adding short chain alcohol, oil and fat, and obtained lipase enzyme complex in a reaction vessel and reacting the mixture at 30-50 degrees C for 48-72 hours to obtain product.