Polyethylene-based composites were prepared using keratin fibers obtained from chicken feathers. Fibers of similar diameter but varying aspect ratio were mixed into low-density polyethylene (LDPE) using a Brabender mixing head. From uniaxial tensile testing, an elastic modulus and yield stress increase of the composite over the virgin polymer was observed over a wide range of fiber loading. Scanning electron microscopy revealed some interaction between the polymer and keratin feather fiber. In addition, the keratin fiber had a density lower than the LDPE used in this study resulting in composite materials of reduced density. The results obtained from mechanical testing are compared to theoretical predictions based on a simple composite material micromechanical model.