The invention relates to a preparation method for a density-controllable light bamboo-wood-based 
fiber plate. The method comprises the steps that firstly, thermosetting phenolic resin is prepared; secondly, bamboo 
powder phenolic 
resin composite foam particles are prepared, then, fir wood 
fiber, paraffin and the bamboo 
powder phenolic 
resin composite foam particles are placed into a mixer, next, amodified 
urea-
formaldehyde resin adhesive is sprayed, and paving is performed after the mixture is uniformly stirred; thirdly, the mixture is placed into a pre-presser for prepressing, and then the product is moved into a 
hot press to be subjected to hot-pressing treatment; and finally, the product is subjected to pressure relief, cooling, plate 
cutting and maintenance, and the density-controllable light bamboo-wood-based 
fiber plate is obtained. According to the method, bamboo 
powder and the phenolic resin are processed into a foam particle composite 
system by means of the special treatmenttechnology, and the foam particle composite 
system is used for replacing a part of layer structures of the fiber plate material; and the purpose of weight reduction is achieved by enhancing the 
porosity of the original 
material system, the complexity of the 
processing technique is effectively lowered, and the 
controllability of the 
processing technique and the regulation of the product density areimproved.