The invention belongs to the field of a lithium ion battery material, and discloses a titanium dioxide-copper oxide nano compound and a preparation method and an application thereof. The preparation method comprises the steps of adding nanometer TiO<2> and Cu(Ac)<2>.H<2>O into a solvent, and performing ultrasonic treatment, stirring and mixing uniformly to obtain a turbid liquid; next, dropwise adding stronger ammonia water to adjust PH to be alkali, heating to 85-95 DEG C and reacting for 10-15h, and performing natural cooling after the reaction is completed; and performing washing and dryingon the obtained solid product, and next, performing calcining in the air atmosphere at a temperature of 300-450 DEG C for 3-8h to obtain the titanium dioxide-copper oxide nano compound. The preparation method is simple and easy to implement, and energy-saving and environment friendly; and the obtained TiO<2>-CuO nanometer compound, when used as the negative electrode material of the lithium ion battery, is excellent in electrochemical performance.