High-density polyethylene (HDPE)-wood composite samples were prepared using a twin-screw extruder. Improved filler-filler interaction was achieved by increasing the wood content, whereas improved polymer-filler interaction was obtained by adding the comatibilizer and increasing the melt index of HDPE, respectively. Then, effects of filler-filler and polymer-filler interactions on dynamic rheological and mechanical properties of the composites were investigated. The results demonstrated that enhanced filler-filler interaction induced the agglomeration of wood particles, which increased the storage