The present invention discloses a method for preparing Triclabendazole comprising condensing N-(4,5-dichloro-2-ni-trophenyl)acetamide with 2,3-dichlorophenol to obtain 4-chloro-5(2,3-dichlorophenoxy)-2-nitrophenyl acetamide and it to obtain 4-chloro-5(2,3-dichlorophenoxy)-2-nitroaniline reducing 4-chloro-5(2,3-dichlorophenoxy)-2-nitroaniline in presence of Raney nickel to obtain 4-chloro-5-(2,3-dichlorophenoxy)benzene-1,2-diamine of cyclising 4-chloro-5-(2,3-dichlorophenoxy)benzene-1,2-diamine in presence of carbondisulfide to obtain 6-chloro-5-(2,3-dichlorophenoxy)-1H-benzimidazole-2-thiol methylating 6-chloro-5-(2,3-dichlorophenoxy)-1H-benzimidazole-2-thiol using a methylating agent to obtain triclabendazole methanesulfonate salt converting triclabendazole methanesulfonate salt to hydrochloride salt of Triclabendazole and hydrolysing it to obtain Triclabendazole.
