To provide steel cords that have excellent rubber penetrability, as it maintains its required strength, and has excellent fatigue resistance, scarcely occurring buckling, even after undergoing repetitive bending load, and steel radial tires having prolonged life time.

In the steel cords having a single layer open-twisting structure (1×n, where n is 7 or 8) that are buried in a rubber-molded product, when it is used, the flatness ratio D1/D2 is controlled in the range from 1.2-2.5 and one wire has a smaller part than the other surrounding wires at a ratio of once per 2-50 pitches and deviates toward the cord core.