PURPOSE: To produce an electric resistance welded tube excellent in sulfide stress corrosion cracking resistance.

CONSTITUTION: In an electric resistance welded tube produced by steel having a basal compsn. of 0.05 to 0.35% C, 0.50 to 2.50% Si, 0.30 to 2.00%Mn, 0.0005 to 0.0080% Ca and 0.005 to 0.100% Al and contg., at need, one or ≤two kindsamong Mo, Nb, V, Ti, B, Cu, Ni and Cr, among oxide inclusions contained within 100μm on both sides around the electric resistance welded abutting face, as the shape of the inclusions viewed in the cross section, the ratio of the length in the thick plate direction to the length in the circumferential direction is regulated to ≤2, furthermore, the number of inclusions having ≥10μm major axis to cut the cross section per mm2 is regulated to ≤5, moreover, around the electric resistance welded abutting face, the measured value of the hardness within 30mm on both sides is regulated to ≤250 by Vickers hardness, and the hardness of the softest phase in the same area is regulated to ≥100 by Vicker hardness.