The invention relates to an intermediate 2-n-propyl-4 methyl-6-(methyl benzimidazole-2- radical) benzimidazole salt for high blood pressure resistance medicine that is telmisartan and the preparationmethod thereof. The intermediate has no any reports in the literature. The invention has the advantages of easy control of the preparation reaction condition, easy getting of raw material, and being suitable for mass production. The intermediate can be used for preparing the telmisartan.