The invention discloses high-strength abrasion-resistant steel for engineering machinery and a manufacturing method thereof. Components of the steel includes, by weight, 0.05-0.30% of C, 0.20-0.65% of Si, 1.20 to 1.60% of Mn, S<=0.010%, P<=0.020%, 0.0010-0.0040% of B, 0.30-1.00% of Cr, 0.030-0.080% of V, 0.015-0.050% of Al, [N]: 80-(200*10-6), [H]<=2*10-6, [O]<=40*10-6, and the balance Fe and inevitable impurities. The steel has surface brinell hardness no less than 395HBW, tensile strength no less than 1220 MPa, elongation after fracture no less than 13% and -20 DEG C shock absorption energy no less than 70J and is low in cost and capable of being used for manufacturing high-strength and high-abrasion resistance mechanical products in the industries of engineering, mining, building, agriculture, cement production, harbors, electric power and metallurgy. For example, the steel can be used as steel balls and lining plates of a ball grinder, bucket teeth of an excavator, rolling mortar walls, toothed plates and hammers of various crushers, track shoes of a tractor and a tank, scraper knives and relieving teeth for a bulldozer and the like.