It is known that surface modified magnetic nanoparticles have been suggested as a support for the immobilization of enzyme. The surface of magnetic nanopariticle was modified with surfactant such as sodium dodecyl sulfate (SDS) and alkyl benzenesulfonate (ABS) to immobilize lipase using physical adsorption affinity. The surfactant is attached to the magnetite nanoparticles via a chelation of sulfate group of SDS or sulfonate of ABS. Samples are characterized by various techniques. Transmission electron microscope showed that magnetic nanoparticles had an average size of 10„b2 nm. Magnetic measurement revealed that the magnetic silica nanoparticles were superparamagnetic and the saturation magnetization was about 68-77 emu/g. Porcine Pancreas Lipase (PPL) was immobilized onto the nano particles by physisorption, which was to catalyze hydrolysis of olive oil, showed enhanced durability in the repeated use and catalytic activity was found to be higher than that of free enzyme. Candida Rugosa Lipase (CRL) was also immobilized, however, activity of immobilized lipase was found to be less than that of free enzyme. Since the immobilized superparamagnetic nanoparticles could be easily recovered by magnet, their adsorption affinity and catalytic affinity were compared to each other by using reusability.