The invention provides a preparation of a halogen-containing polymer and a method for catalytic oxidation of alcohol to aldehyde and ketone by virtue of the halogen-containing polymer as a catalyst of an oxidation reaction and relates to the technical field of synthesis of an important organic intermediate, namely steroids. The invention discloses a preparation method of the halogen-containing polymer. The method for catalytic oxidation of alcohol to aldehyde and ketone by virtue of the halogen-containing polymer as the catalyst of the oxidation reaction comprises the steps of reacting alcohol compounds with hydrogen peroxide, sodium hypochlorite, potassium persulfate complex salt, peracetic acid, t-butylhydroperoxide and the like as green oxidizing agents in the presence of the halogen-containing polymer as a catalyst and a solvent at (-30)-150 DEG C, after the reaction is completed, recovering a halogen-containing polymeric catalytic oxidizing agent by virtue of simple filtration and carrying out liquid separation treatment on the filtrate to obtain the target compound. The method is efficient, clean and environment-friendly and also has the advantages that components in the system are simple, the catalyst is stable, easily recovered and can be repeatedly used for at least 20 times.