The invention discloses a steel bar applicable to concrete. The steel bar comprises a steel bar body and a plurality of transverse ribs, wherein the transverse ribs are projected out of the steel bar body; the maximum dimension of the cross section of the steel bar body is d; the maximum dimension of the transverse ribs projected out of the steel bar body is h; the width of the transverse ribs projected out of the top of the steel bar body is defined into a rib top width b; the distance between the two adjacent transverse ribs in the length direction of the steel bar body is defined into a rib space L; the transverse ribs are divided into two groups and are respectively arranged at the two sides of the steel bar body; the part, positioned between the two groups of transverse ribs, of the cross section of the steel bar body is a smooth curve or/and straight line; the value range of the maximum dimension h of the transverse ribs projected out of the steel bar body is 0.03d to 0.2d; the value range of the rib top width b is between 0.04d and 0.1d. The steel bar has the beneficial effects that through the improvement on the steel bar shape and the dimension parameters, the steel bar body has the smoother outline; the structure with cracking risk during the combination with the concrete is eliminated, so that the firmness degree of the reinforced concrete formed by the steel bar is improved.