The plastics and ceramics have been the dominant and emerging composite materials in the last four decades. The tremendous increase of production and use of plastics in every sector of our life lead to huge plastic wastes. But now, the industry is attempting to decrease the dependence on synthetic materials. Natural fiber composite materials are gaining industrial interest in a world focused on engineering challenges. The modern research has suggested that natural fiber reinforced composites proves to better than other materials. This is leading to the need to investigate environmentally friendly, sustainable composite materials to replace other ones. Several innovative manufacturing techniques are being applied in order to meet this challenge. The current challenge is to develop natural composite materials, which would be economically attractive and cost effective. The present book is primarly based on analysis of tensile and flexural behavior of hemp fiber reinforced with fresh plus recycled high density polyethylene based natural fiber composite.