In order to obtain green and insensitive high energy explosives, 50 grams-scale synthetic method of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was investigated. The key intermediate of 5,5′-bistetrazole-1,1′-diol dihydrate (1,1′-BTO) was synthesized through oximation, chlorination, azidation and cyclization from glyoxal. TKX-50 was successfully obtained from the reaction of 1, 1-BTD with hydroxylamine aqueous solution. The product was characterized by ¹H NMR, IR, MS, DSC and element analysis. In the preparation process of TKX-50 from 1,1′-BTO, the influence of molar ratio of reactants, reaction time and temperature on the yield of TKX-50 were studied. The optimal conditions of the process were determined: when the reaction was operated at 80 ℃ for 1h with the molar ratio of n(1,1′-BTO):n(NH₂OH·HCl):n(NaOH) = 1:2.2:2.2. The yield could achieve in 80.1%. The total yield of the synthetic route is 41.5 %. The technology is valuable for the preparation of TKX-50 in large scale.