The invention relates to a preparation method of three-dimensional nano porous tin-base alloy for a lithium-ion battery negative electrode. Within the temperature range between 0 and 100 DEG C, a transitional metal cyanide aqueous solution in given concentration is mixed and reacted with a stannic chloride aqueous solution in given concentration to form a tin-base cyanogen gel system according to certain molar ratio. The tin-base cyanogen gel system is used as a precursor, a reducing agent in identical volume or excessive volume is added into the precursor to stand for 0.1 to 20 hours, the tin-base cyanogen gel is adequately reacted with the reducing agent, and a product is washed and dried under the protection of vacuum or inert gas to obtain the three-dimensional nano porous tin-base alloy. The three-dimensional nano porous tin-base alloy prepared by adopting the tin-base cyanogen gel system as the precursor is used as the lithium-ion battery negative electrode material, the tin-base alloy has a three-dimensional nano porous structure, and when being used as the lithium-ion battery negative electrode material, the tin-base alloy has good cycling performance, high specific capacity and multiplying power performance. The preparation method is simple and environment-friendly, and the mass production can be realized.