Blending of ultrahigh molecular weight polyethylene (UHMWPE) and linear low density polyethylene (LLDPE) could be done by mixing UHMWPE and LLDPE. The mixer was used for dry blending and melt blending. The compositions of blended polymers were 5, 10, 30, 50, 70, 90, 95, 100% UHMWPE. The processing was done by an injection process. Differential scanning calorimetry and scanning electron microscopy was used to determine the compatibility. These were found that blended polymers had good compatibility for each composition. Mechanical properties, which were impact strength and tensile strength were studied. Impact strength could not be done since blended polymers had high toughness and fatigue. Tensile strength increased when %UHMWPE increased. Shrinkage measurement and cost consideration were studied. Shrinkage and cost decreased when %LLDPE increased. Furthermore the properties of blended polymers could be improved by fillers. Glass fiber and talcum were used as fillers. The amount of fillers was 30%. It was found that the composite polymers had higher impact strength and tensile strength than that of blended polymer. Additionally, glass fiber and talcum decreased shrinkage of blended polymers. Shrinkage of the composite polymer was dramatically decreased when using talcum as fillber. The cost of the composite polymers was decreased 25% and 30% by using the glass fiber and talcum respectively.