The invention discloses a high strength and toughness guide rail steel, and the high strength and toughness guide rail steel comprises, by mass, 0.46-0.57% of C, 3.60-4.50% of Si, 4.5-5.1% of Mn, no more than 0.010% of P, no more than 0.010% of S, 2.2-2.7% of Ni, 2.5-3.5% of Cr, 2.5-3.5% of Co, and the balance Fe. According to the high strength and toughness guide rail steel, design of high silicon, high manganese and high cobalt components is firstly proposed, composition and structure of the steel are optimized, obtained steel has high strength and good toughness, guiding requirements of rubber wheel guide rail under the action of small radius curve and high shear force are met, that the rail does not break is ensured, development needs of urban rail transit are met, support is providedfor solving urban congestion, reducing vehicle emissions, and developing China new public environmental protection mode; and a referred preparation method is simple, low energy consumption, and suitable for popularization and application.