The invention discloses a method for preparing vinyl monomers and vinyl chloride monomers. According to the method, the vinyl monomers and vinyl chloride monomers are synthesized by the reaction of methane, chloromethane and oxygen in presence of catalysts for oxidative coupling of methane, and the mole ratio of the sum of methane and chloromethane to oxygen is 1:(0.1-2), the mole ratio of methane to chloromethane is 1:(0.01-5); the reaction temperature of the reaction is 500-900 DEG C, and the reaction pressure of the reaction is 1-10 atm. The method has the advantages of wide raw material sources, low cost, the method is a novel technology for preparing vinyl monomers and vinyl chloride monomers, and is suitable for popularization and application.