There is a distinct need in the composites industry to drive the replacement of heavy metallic components with lightweight polymer composites. Polyketone is a relatively new thermoplastic polymer associated with high mechanical properties of high performance engineering thermoplastics while remaining similar in cost to commodity thermoplastics. Glass fiber reinforced polyketones are excellent candidates for large production environments where mechanical performance at high temperature is necessary. The properties of composite materials greatly depend on the interfacial adhesion which governs the effectiveness of the stress transfer from the polymer to the fiber. This research focuses on studying the interfacial properties of two aliphatic polyketones, with different viscosities, and four glass fibers, with different commercial sizings. We report on the interfacial adhesion as measured by the single fiber pullout test and correlate these properties to the tensile strength of injection molded composite dogbones. Further analysis includes the examination of the composite morphology by scanning electron microscopy.