The invention relates to a preparation method of an anti-bacterial buffering composite packaging material based on camellia oleifera shells. The preparation method includes the steps of: 1) fully and uniformly stirring 100 parts by weight of pretreated camellia oleifera shell powder, 6-12 parts by weight of a plasticizer, and 5-10 parts by weight of an adhesive, adding 3-10 parts by weight a compound foamer and 3-8 parts by weight of a filler and fully and uniformly stirring the components, pouring the mixture into a mold and placing the mold in a drying box; and 2) foaming the mixture at 100-120 DEG C for 10-30 min and drying the mixture at 90-110 DEG C to prepare the packaging material. Compared with the prior art, the packaging material has the advantages as follows: (1) with the waste camellia oleifera shell as a raw material, which is wide in source, the packaging material is low in cost and is beneficial to comprehensive utilization of the camellia oleifera shell; (2) the preparation method is simple and low-cost, and the packaging material has high adsorption capacity and is wide in application range; and (3) the method has mild reaction conditions and is easy to control, has simple modification process, is less in technical equipment, and is simple to carry out.