Belonging to the technical field of steel for railway wheels, the invention relates to a high strength and high toughness heavy haul train wheel steel and a heat treatment method thereof. The steel comprises the following chemical components by weight percentage (wt.%): 0.75-0.85wt.% of C, 0.80-1.00wt.% of Si, 0.40-0.80wt.% of Cr, 0.30-0.50wt.% of Mn, 0.01-0.03wt.% of Nb, 0.02-0.06wt.% of V, 0.010-0.025wt.% of Al, less than 0.015wt.% of P, less than 0.015wt.% of S, and the balance Fe and unavoidable impurities. After conventional smelting, casting and forging, a wheel is subjected to a novel heat treatment process adopting tread quenching and sub-sectional cooling. After heat treatment, the structure at a standard tensile test position of a rim is a fully lamellar perlite structure, the size of a pearlite colony is 2-6microm, and the pearlite interlamellar spacing is 0.05-0.09microm. The room temperature tensile strength of the rim is 1200MPa grade, the percentage elongation after fracture is greater than 12%, and the web 20DEG C impact energy KU2 is greater than 20J. Therefore, the high strength and high toughness heavy haul train wheel steel has excellent strength and toughness matching, and can be used for heavy haul trains.