To obtain a high strength high corrosion resistance seamless steel tube, which is excellent in SSC resistance, has a high yield point and is usable for an oil well and its related equipment by subjecting a billet having a specified element composition to piercing/stretch rolling under a specified condition and then direct quenching/tempering after auxiliary heating treatment.

A billet has a composition consisting of, by weight, 0.2-0.35% C, 0.05-0.5% Si, 1-5% Mn, 0.2-1% Mo, 0.005-0.5% Ti, 0.0001-0.1% B, 0.005-0.1% Nb, 0.005-0.5% sol. Al, others of Cr, V, W, Zr, Ca and the balance Fe with inevitable impurities, further P, S, Ni, O in the impurities of specified quantity or lower. When piercing/stretch rolling the billet in hot, after the billet, in a final finish rolling, is rolled at a thickness reduction ratio of ≥40% in a range of 850-1100°C, an auxiliary treatment to heat/hold in the temp. range for 10 sec-30 min is conducted. Further direct quenching is conducted and then tempering.