To provide a method for processing waste wood and/or waste bamboo and waste oil difficult to be disposed to obtain a fuel having excellent transportability and fluidity and high combustion calorie.

The method for the treatment of waste wood 6 and waste oil 10 comprises the immersion of the waste wood 6 in a heated waste oil 10 to effect the dry distillation and carbonization of the waste wood 6 and the adsorption of the oil to the produced carbonized product 7. A fuel having fluidity and high combustion calorie can be produced by crushing the carbonized product 7 containing adsorbed oil. The product is easily handleable because the powder of carbonized product containing adsorbed oil is scarcely diffusible in air to lower the risk of powder explosion.