The invention discloses a testing method for the adhesive force of RTV (Room Temperature Vulcanization) anti-pollution-flashover paint. The RTV anti-pollution-flashover paint contains a silane coupling agent; a product to be tested comprises a base material and an RTV anti-pollution-flashover paint coating adhered on the base material, and a circling method or a griding method is adopted. The testing method comprises the following steps: (1) carrying out testing under the ambient temperature, wherein when the product to be tested is used for a sampling test or a type test, if the adhesive force corresponds to 1-2 level in the circling method or 0-1 level in the griding method, the product is proved to be qualified, and the step (2) is carried out, otherwise the product is proved to be unqualified; when the product to be tested is an insulator under the operating state, if the adhesive force corresponds to 1-3 level in the circling method or 0-2 level in the griding method, the product is proved to be qualified, and the step (2) is carried out, otherwise the product is proved to be unqualified; (2) acting on the product to be tested for 5-6 hours at the temperature of 200-230 DEG C, and taking out to carry out testing within 10 minutes, wherein if the adhesive force corresponds to 1-4 level in the circling method or 0-3 level in the griding method, the adhesive force is proved to be good, otherwise the adhesive force is proved to be poor. The testing method disclosed by the invention has the advantage that a more-accurate adhesive force testing result can be provided.