A solid wire contains C of 0.020 to 0.100 mass percent, Si of 0.25 to 1.10 mass percent, Mn of 1.20 to 1.65 mass percent, P of 0.008 to 0.017 mass percent, S of 0.045 to 0.150 mass percent, O of 0.0050 mass percent or less, N of 0.0050 mass percent or less, wherein P*(O+N)*105≦15 is satisfied, and the remainder including Fe and impurities, wherein the relevant impurities contain Ti of 0.15 mass percent or less, B of 0.0050 mass percent or less, and Cr, Ni, Al, Nb, V, Zr, La and Ce of 0.20 mass percent or less respectively. According to such a configuration, a solid wire is provided, in which while increase in welding cost is controlled to the minimum, stability of wire feed, burn-through resistance, undercut resistance, and crack resistance are excellent, slag and spatter are hardly produced, hardness of weld metal is equal to or higher than that of base metal, and brittle fracture hardly occurs.