The invention belongs to the technical field of lithium ion batteries and particularly relates to a negative electrode composite material for a lithium ion battery. The composite material has a core-shell structure containing a core layer and a shell layer, wherein the core layer is a mixture of titanium dioxide and silicon dioxide in a mass ratio of (0.1-10) to 1; the shell layer is made from a carbon material and accounts for 5-20wt% of the composite material. According to the negative electrode composite material provided by the invention, by coating the surface of titanium dioxide and silicon dioxide with the carbon material, on the one hand, the core layer is the mixture of titanium dioxide and silicon dioxide which mutually penetrate each other, so that volume expansion of the whole negative electrode material in the charge and discharge process can be reduced to a certain extent, and moreover, expansion of the negative electrode material can be limited to a certain extent due to the carbon material of the shell layer; on the other hand, the ion conductivity and the electron conductivity of the negative electrode material can be improved due to the carbon material of the shell layer. Therefore, the lithium ion battery containing the composite material is excellent in cycle performance and rate capability.