The invention discloses a method for preparing a doping porous silicon ball. The method includes the steps that a silicon ball with certain doping content is selected, after being washed by hydrofluoric acid, the silicon ball is immersed in solutions formed by nitrate and hydrofluoric acid, after ultrasonic processing is carried out, the silicon ball is immersed in solutions prepared by the hydrofluoric acid and oxidizing agents and reacts at a certain temperature for a certain time period, then the silicon ball is washed in a centrifugal mode, and ultimately the nano porous silicon ball is prepared after nitric acid washing and other post-processing procedures. The best variety and the best concentration of reaction solutions, the optimum proportion of components, the best reaction temperature, the best reaction time, best ultrasonic frequency and best ultrasonic processing time are screened out through a large quantity of experiments. According to the whole preparation method, process design is reasonable, operability is high, production cost is low, production efficiency is high, and large-scale industrial production can be achieved. According to the high-purity doping porous silicon ball prepared in the method, the shapes of holes are regular, the holes are uniformly distributed and honeycomb-shaped, the shape of the silicon ball is regular, and the method can be widely used in the field of lithium batteries, solar batteries, semi-conductors, sensors and the like.