The invention discloses an industrial preparation method of 
dabigatran, and belongs to the field of 
medicinal chemistry, wherein the preparation method sequentially comprises a 
condensation reaction, a closed cyclization reaction, a Pinner reaction, and other steps. According to the present invention, the 
hydrogen chloride / 
alcohol / ester solution is prepared by using 
acyl chloride and 
alcohol as raw materials, such that the problems of 
corrosion on equipment, high hidden safety danger, environmental 
pollution and the like caused by the use of 
hydrogen chloride gas in the prior art are solved; and the reactions in various steps are subjected to the industrial-scale-based optimization, the unnecessary 
distillation, extraction and re-
crystallization process is reduced, the process is simplified, the purification method of the final product 
dabigatran is improved, the purification efficiency is increased in the case of the ensuring of the process yield and the product quality, the process reproducibility is good, the preparation cost is low, and the method is the ideal industrial preparation method of the 
dabigatran.