Biocomposite scaffolds consist of poly(lactic-co-glycolic acid) and wool keratin were obtained by an electrospinning process. Scanning electron microscopy images showed that the poly(lactic-co-glycolic acid)/wool keratin fibers had relatively rougher surfaces and smaller diameters. Thermogravimetric analysis showed higher thermal stabilities of the developed biocomposites compared to neat poly(lactic-co-glycolic acid). Mechanical tests showed that when the wool keratin content increased from 0% to 0.5% w/v, the tensile strength and elongation at break of the poly(lactic-co-glycolic acid)/0.5% wool keratin scaffolds increased with maxima of 6.59 MPa and 104.44%, respectively, which was an increase of 8.2% and 570% over the poly(lactic-co-glycolic acid) scaffold. The biological response of bone mesenchymal stem cells to the poly(lactic-co-glycolic acid)/1.5% wool keratin biocomposites was superior when compared to pure poly(lactic-co-glycolic acid) scaffold in terms of improved cell attachment and higher proliferation. These observations suggest that the addition of wool keratin to a poly(lactic-co-glycolic acid) matrix can improve several properties of the electrospun poly(lactic-co-glycolic acid) fibers, and the poly(lactic-co-glycolic acid)/wool keratin biocomposites could make excellent materials for tissue engineering applications.