Abstract: A novel method for the synthesis of molecular probe of ubiquinone binding protein is described. With 3 nitrosalicylic acid and decylamine as initial compounds and under the existence of DCC, the 3 nitrosalicyl N (n decyl)amide is synthesized at room temperature. Then, 3 nitrosalicyl N (n decyl)amide is reduced by hydrogen with 5 % Pd/C as catalist to form 3 aminosalicyl N (n decyl)amide which is exchanged with tritium to be 3H 3 aminosalicyl N (n decyl)amide. At the temperature below 5 ℃, 3H 3 aminosalicyl N (n decyl)amide reacts with NaNO 2 and HCl, and the 3 diazosalicyl N (n decyl)amide is formed in an ice salt bath. As soon as the reaction is completed, NaN 3 is added to the mixture and stirred for 3 h at the temperature between 0～5 ℃ and in the dark, the molecular probe of studying ubiquinone binding protein, i. e., 3H 3 azidosalicyl N (n decyl)amide is produced.