NOVELTY - A nano sodium ion (Na+) doped lithium titanate preparing method involves mixing a surfactant, co-surfactant and deionized water, and stirring the mixed solution. Solution B preparation process is performed by mixing lithium and sodium, and adding deionized water. The solution B is added to the solution A and heated. Soluble titanium compound:(lithium and sodium) are dissolved in cyclohexane. The microemulsion is placed on a magnetic stirrer and adding solution C. After aging the product, the product is centrifuged, washed and dried. The white sample is washed, centrifuged, dried and heat treated.    USE - Method for preparing nano sodium ion doped lithium titanate (claimed) in the field of civil portable electronic device and power device field.    ADVANTAGE - The method enables preparing nano sodium ion doped lithium titanate with better particle agglomeration phenomenon, improved and better control of particle diameter size, high charge and discharge circuit, and improved circulation performance.    DETAILED DESCRIPTION - A nano sodium ion (Na+) doped lithium titanate preparing method involves mixing a surfactant, co-surfactant and deionized water with mass ratio of 1-3:1:30 to give a mixed solution, and magnetically stirring the mixed solution at room temperature, so that the solution is clear to obtain solution A. Solution B preparation process is performed by mixing lithium and sodium sparingly soluble or soluble compound with a molar ratio of 3.9-3.98:0.02-0.1, and adding an appropriate amount of deionized water to obtain a solution B. The solution B is added to the solution A, heated under water bath with magnetic stirring to obtain a uniform transparent microemulsion. Soluble titanium compound:(lithium and sodium) (5:4) are dissolved in cyclohexane to give the solution C, where the mass ratio of titanium source and cyclohexane is 5:(1-3). The microemulsion is placed on a magnetic stirrer water bath, slowly stirred during the dropwise addition of the solution C, and continued constant stirred to react. After aging the product, the product is centrifuged under high-speed centrifuge, washed with organic solvent, and the washed product is vacuum dried to give a white sample. The white sample is ultrasound acid washed to remove residual sample of a compound of lithium and sodium, centrifuged and dried to give the pure sodium lithium titanate powders and heat treated in an air atmosphere to obtain sodium lithium titanate.