The invention provides a method for preparing a catalyst for catalyzing oxidation of cyclohexane. The method comprises steps as follows: (A), preparing 5 (p-propionate) phenyl-10,15,20-tri(pyridyl) porphyrin; (B), preparing 5(p-hydroxy) phenyl-10,15,20-tri(pyridyl) porphyrin from 5 (p-propionate) phenyl-10,15,20-tri(pyridyl) porphyrin; (C), preparing metallic coordinated 5-(p-hydroxy) phenyl-10,15,20-tri(pyridyl) porphyrin from 5 (p-hydroxy) phenyl-10,15,20-tri(pyridyl) porphyrin; (D), attaching the metallic coordinated 5-(p-hydroxy) phenyl-10,15,20-tri(pyridyl) porphyrin to at least one magnetic microsphere, and methylating 5-(p-hydroxy) phenyl-10,15,20-tri(pyridyl) porphyrin by the aid of methyl iodide.