The present invention relates to a plant fiber material having excellent dispersibility, for use as a reinforcing material for a matrix resin. Provided are a method for producing a plant fiber composite material to be kneaded with a matrix comprising the steps of: maintaining plant fibers in the state of floating and being dispersed in air in a container; supplying and attaching fine droplets of a wax fine particle dispersion to the surface of the plant fibers; and collecting the plant fiber composite material comprising wax-attached plant fibers, of which each surface is coated with wax fine particles; and a plant fiber composite material to be kneaded with a matrix, which comprises wax-attached plant fibers produced by the method.