The invention relates to a high-strength high-toughness abrasion-resistant cast steel material and a preparation method thereof. The novel high-strength high-toughness abrasion-resistant cast steel material is pertinently designed and developed for the severe working conditions that in the operation process, a trough side not only bears violent friction of coal, a scraper blade and a chain, but also bears operation load of a coal cutter, lateral force and longitudinal force used for pushing and pulling a hydraulic support, extrusion force and impact force generated when large sized coal and rock get stuck in a trough and the like. According to the mechanical performance indexes the cast steel material can reach, the tensile strength Rm>=900 MPa, the fracture elongation A>=16%, the impact absorbing energy Aku>=32J, and the Brinell hardness HB is 270-310. According to the abrasion resistance, weightlessness is 1.55+/-0.03 g, and the weight loss ratio is 15.5+/-0.3 mg/m. According to the preparation method, production is easy, the cost is low, and the performance is high. Quantity production and application can be achieved in the industries such as mines, energy, transportation, agricultural machinery and engineering machinery.