The invention relates to a bamboo charcoal modification method applicable to oily wastewater treatment. The bamboo charcoal modification method comprises the steps: adding bamboo charcoal into a silane coupling agent ethanol solution so as to enable a silane coupling agent and hydroxyl groups on the surface of the bamboo charcoal to generate conjugation reaction, then separating, washing and drying the reacted bamboo charcoal, thus obtaining modified bamboo charcoal. Compared with the prior art, the bamboo charcoal modification method overcomes the defects that an existing commonly used coarse-grained filler modification method is infirm for the conjugation between hydrophobic substances and materials and has a great limit on the materials and the like; through contact angle tests and oil removal tests, the hydrophobicity of the modified bamboo charcoal is enhanced, the oil removal rate can be increased by 13%, and a resource approach can be provided for bamboo processing wastes.