A cemented carbide comprises particles including a tungsten carbide (WC) as a main component; a binder phase including cobalt (Co) as a main component; and particles including a carbide or a carbonitride of at least one selected from the group consisting of Group 4a, 5a, and 6a elements, or a solid solution thereof, wherein a cubic phase free layer (CFL), in which the carbide or the carbonitride is not formed, is formed from a surface of the cemented carbide to a depth of 5 μm to 50 μm.