A steel cord having a two-layer twist structure provided with a core in which two or three core filaments are twisted together and one layer of an outer sheath in which outer sheath filaments are twisted together in a spiral shape along the longitudinal direction of the core around the core. The core filaments and the outer sheath filaments have the same filament diameter. The core and the outer sheath have the same twist pitch. The twist pitch/filament diameter ratio, which is the ratio between the twist pitch and the filament diameter, is 50-75 inclusive. Two or more filaments selected from among the core filaments and the outer sheath filaments are waved filaments repeatedly having bent parts and non-bent parts along the longitudinal direction.