This work investigates the feasibility of using recycled high density polyethylene (rHDPE), recycled polypropylene (rPP) and old newsprint fiber (ONP) to manufacture fiber reinforced composites. The boards were made through air-forming and hot press. The effects of the fiber loading and coupling agent content on tensile, flexural, internal bond properties and water absorption and thickness swelling of wood-fiber plastic composites were studied. In general, the weight content of ONP is a key parameter that would substantially influence the physical and mechanical properties of the samples. The obtained results showed that the use of maleated polypropylene as coupling agent, improved the compatibility between the fiber and both plastic matrices, and mechanical properties of the resultant composites compared well with those of non-coupled ones. Based on the findings in this study, it appears that recycled materials can be used to manufacture value-added boards without having any significant adverse influence on board properties. It was also found that composites with rHDPE provided moderately superior properties, compared with rPP samples.