In this research, the polymer composites based on high density polyethylene (HDPE) resin and wood flour using the PEgMA compatibilizer and rutile titanium dioxide (TiO2) nanoparticles were prepared by melt-mixing method in a Haake internal mixer. In the presence of 4 wt. percent of the compatibilizer and 1 wt. percent of modifies TiO2 nanoparticles in the compositions of the HDPE/WF composite (with 50 wt. percent of wood flours) increased the tensile strength up to a highest value of 32.51 MPa. The structural morphology was studied by using a field emission scanning electron microscopy (FE-SEM) clearly indicated the leading roles of compatibilizer and inorganic nanoparticles contributing to the enhancement of the flexural strength and minimizing the soak of the composite material as well. The addition a small content of (1 wt. percent) TiO2 nanoparticles increased significantly the melting viscosity of composite mixture, therefore, assisting the processibility of pressing-extrusion technique.