A steel cord is configured so that, when the steel cord is used as a tensile cord for an elastic crawler, a center-core dislocation and the early breakage of the wires of a core are prevented. A steel cord comprises: a core which comprises a single core strand, and a sheath which is formed by twisting together six sheath strands arranged around the core. The core strand has a layer-twisted structure comprising: a center-core portion which is formed by twisting three core wires together; and an external layer portion which is formed by twisting together eight to nine core wires arranged around the center-core portion. The sheath strands each have either a bundle twisted structure which is formed by twisting twelve to nineteen sheath wires or a multi-layer twisted structure which is formed by twisting twelve to nineteen sheath wires in layers. The diameter (dc) of the core wires is greater than the diameter (ds) of the sheath wi res. The average gap (Gc) between the core wi res of the external layer portion is 0.015 mm or greater, and the average gap (Gs) between the sheath strands is 0.1 mm or greater.