High-strength and low-temperature-resistant steel and production method thereof

The invention discloses high-strength and low-temperature-resistant steel. The high-strength and low-temperature-resistant steel is composed of, by mass, 0.05-0.2% of C, 0.1-0.26% of Si, 0.60-8.00% of Mn, 0.4-0.8% of Cr, 0.12-0.28% of Mo, not larger than 0.03% of Cu, 0.02-0.06% of Al, 0.010-0.018% of Ti, not larger than 0.012% of P, not larger than 0.005% of S, 0.004-0.01% of N, not larger than 0.0012% of O, not larger than 0.00012% of H, 0.001-0.005% of Ca, 0.0001-0.0005% of Sb, not larger than 0.001% of Sn, not larger than 0.005% of As, not larger than 0.0010% of B, not larger than 0.08% of V, not larger than 0.03% of Nb and the balance Fe. The low-temperature impacting power of the finished product steel is obviously improved, the impacting power value is 260-350 J at the temperature of -20 DEG C, and the impacting power value is 240-300 J at the temperature of -40 DEG C.