The invention discloses high-strength, high-toughness and good-weldability steel for mine machinery and a production method of the steel. The steel for mine machinery comprises, by mass, 0.22-0.29% ofC, 0.16-0.30% of Si, 0.35-0.60% of Mn, 1.24-1.58% of Cr, 1.20-1.60% of Ni, 0.23-0.30% of Mo, 0.021-0.035% of Al, 0-0.020% of P, 0-0.015% of S and the balance Fe and inevitable impurities. The production method comprises the treatment processes of smelting, continuous casting, heating, rolling and tempering. The chemical components are matched, Ni ensures high toughness, Cr, Ni, Mo and the like ensure high strength, the content of C is reduced to improve the weldability, the problem that similar steel cannot achieve high strength, high toughness and good weldability at the same time is solved,and the requirement of the mine machinery for the steel is met.