According to the environmental limits and issues of fossil fuels which are also non-renewable, using alternative energy resources has become increasingly important. To replace fossil fuels, the increase in biodiesel production as a biofuel has made us to pay more attention to the production process optimization; so that not only it is capable of producing in large quantities but also has a simple and clean production process and reduces waste production to its lowest level. The purpose of this study is to synthesize magnetic nanocomposites based on graphene oxide for the lipase immobilization to produce biodiesel. In that regard, the graphene oxide sheets coated with nickel ferrite magnetic nanoparticles (NiFe 2 O 4 -GO) and used for enzyme immobilization. The VSM, XR, SEM, EDS and FTIR analyses were performed to find and confirm features of the nanoparticles, graphene oxide and synthesized magnetic nanocomposite and it was shown that nanoparticles are successfully synthesized and immobilized to graphene oxide. Furthermore, lipase from candida rugosa was immobilized on the synthesized base. The lipase immobilization process was studied using different enzyme concentrations (30, 60, 100, 130 and 160 µg/ml) and different times (1, 2, 3, 4 and 5 h). The enzyme binding on this basis and the immobilized enzyme’s activity level were respectively studied by Bradford protein assay and the p- nitrophenyl laurate ( p -NPL) hydrolysis technique. Based on the best response of the immobilization efficiency and the resulted enzyme activity, 100 µg/ml enzyme concentration and 2 h incubation time were selected as the optimal conditions for the immobilization process. Subsequently, free and immobilized enzymatic activities at various pH values (6, 6.5, 7, 7.5, 8) were studied and the optimal pH values for immobilized and free enzymes was respectively determined 7.5 and 7. Moreover, the activity of free and immobilized enzymes at various temperatures (20, 30, 35, 40, 50 °C) were studied and the optimal values for free and immobilized enzymes was respectively determined 35 and 40 °C. To evaluate thermal resistance and pH stability of free and immobilized enzymes, they were also studied at temperatures of 30, 40, 50 and 60 °C and pH values of 6, 6.5, 7, 7.5, 8 and 9. The results revealed that in comparison to free enzyme, immobilized enzyme is more resistant; so that at the temperature of 60 °C it could retain 70% of its initial activity and lost only 20% of it at pH of 9. Kinetics parameters were calculated studying enzymatic activities value at various concentrations of p -NPL substrate. The values of V max for free and immobilized enzymes were respectively calculated 12 and 6.54 U/mg and the values of K m evaluated 0.61 and 0.7 mM. The immobilized enzyme after each p -NPL substrate hydrolysis was recycled and reused by an external magnet; so that after 6 cycles of hydrolysis, it retained 47% of its initial activity which demonstrates the reusability and resistance of immobilized lipase. Furthermore, due to the numerus abilities for biodiesel production, Scenedesmus obliquus , the microalga was chosen and cultivated. To increase the microalga lipid, scientists have used the two-stage cultivation method and nitrogen deficiency. By applying this method and cultivation conditions: aeration with 3% CO 2 under a photoperiod of 16:8 h light:‌‌dark cycle at light intensity of 25 µmole photons/m 2 .s, there was an increase in the value of microalga lipid from 11.5% to 18%. At the end of the process, after extracting microalgae lipid, free and immobilized lipases were used as biocatalyst for biodiesel production with the methanol to oil molar ratio of 4:1 at 40 °C with mixing speed of 180 rpm for 24 h. The performed reactions were studied by GC-MS technique and biodiesel production efficiency was evaluated. The result has shown that the main parts of biodiesel are fatty acid groups of C16 and C18. Biodiesel production efficiency by using free and immobilized enzymes as a biocatalyst was determined 80.4% and 67.4% respectively. Keywords: Graphene Oxide, Enzyme Immobilization, Lipase, Magnetic Nanoparticles, Nickel Ferrite, Biodiesel, Microalgae, Scenedesmus obliquus