The invention discloses a method for preparing ligustrum lucidum biological activated charcoal. According to the method, three factors, i.e., dipping ratio, activation temperature and activation timeof an independent variable, i.e., zinc chloride, yield of a dependent variable, i.e., activated charcoal and a sulfur dioxide adsorption mathematical model are subjected to regressive analysis by using experimental design software Design-Expert, and an obtained mathematical model is good in fitting property and is accurate and reliable; an experimental result is predicted by replacing an experimental real point with the model, and optimal processing conditions for preparing the activated charcoal through burnetizing ligustrum lucidum are predicted; meanwhile, by adopting a special impurity washing mode, the defect of the conventional activated charcoal production processes that the activated charcoal is acidified due to acid pickling is overcome, and active metal ingredients in the activated charcoal are reserved; and the prepared activated charcoal is particularly applicable to adsorption of acid pickling industrial waste gases, the efficiency of adsorption is high, the waste gas treatment cost is reduced, and then, the application of the activated charcoal in the aspect of treatment of the industrial waste gases is extended.