Transesterificationbetweenmethyl-butyrateand1-butanolinnonaqueoussystemswascatalyzedbyporcinepancreaticlipasewhichwasimmobilizedoncross-linkedpolystyrene.Organicsolvents,substrateconcentration,contentsofwaterandotherparameterswhichaffecttheimmobilizedenzymeactivitywerestudied.Lipaseimmobilizedonhydrophobiccrosslinkedpolystyrenecanreduceitsdiffusionlimitinthereaction.Itwasfoundthattheactivityofimmobilizedlipaseinorganicsystemswastwotimesashighasthatoffreelipase.