Polycrystalline diamond (PCD) drills are commonly employed in carbon fiber-reinforced plastic (CFRP) drilling to satisfy hole quality conditions with an acceptable tool life and productivity. Despite their common use in industry, only a small number of studies have been reported on drilling CFRPs with PCD drills. In this study, drilling performances of three different PCD drill designs are investigated experimentally using thrust force, torque, and hole exit quality measurements. Results show that work material properties, drilling conditions, and drill design should all be considered together during the selection of process parameters, and the relationships among these factors are quite complex.