The work aims to study preparation process of PLA/wood fiber composites, analyze the influence of PLA fiber content on the mechanical properties of the composites, and determine the optimal ratio, in order to obtain a new type of environmental composites which can be used in packaging. Different quality ratios of PLA fiber and wood fiber were made according to the papermaking process, and the wet ground paper was obtained and treated by hot pressing to obtain composite samples. Dispersion of PLA fibers in composites and mechanical properties of composites were characterized and tested. The dispersion test showed that, the PLA fibers could be evenly mixed with the wood fiber. When the mass fraction of PLA fibers was 10%, the composite properties were better. The mechanical test showed that, the maximum tensile strength of composites could reach up to 42.79 MPa, and the folding endurance could reach 1015 times. The PLA/wood fiber composites can be prepared by papermaking method, and their mechanical properties are better. The composites can be widely used in the field of packaging, and also provide a new way of thinking for the research and application of degradable fibers.