The invention belongs to the fields of nanometer materials and nano-technologies and particularly relates to a controllable preparation method of a Cu12Sb4S13 nanocrystalline material. The controllable preparation method comprises steps as follows: 1), the adding proportion of cuprous iodide to antimony chloride to oleylamine is 3 mmol: 1 mmol: 10 mL, cuprous iodide and antimony chloride are added to oleylamine, argon shielding gas is introduced, the temperature is controlled, the components are stirred, cuprous iodide and antimony chloride are enabled to be dissolved completely, and a metal salt complexing solution is obtained; 2), 2-6 mL of 1 mol/L diphenyl ether solution of diphenylthiourea is added to the metal salt complexing solution, and the mixed solution is heated to the set temperature for reaction; 3), the solution is cooled to the room temperature after reaction, methyl alcohol is added for cleaning Cu12Sb4S13 nanocrystalline obtained through the reaction, and the Cu12Sb4S13 nanocrystalline material is obtained. According to the preparation method, the technology is simple, and the cost is low.