The invention relates to a vehicle hydraulic system and an engineering vehicle. The vehicle hydraulic system comprises a first pump, a second pump and a steering control valve. The first pump and the second pump are both driven by an engine of the vehicle. The steering control valve comprises a first reversing valve, a second reversing valve and a pressure control valve and has a first state and a second state. In the first state, an inlet of the first reversing valve communicates with a first outlet of the first reversing valve, an inlet of the second reversing valve communicates with a first outlet of the second reversing valve, and thus the first pump and a second pump both provide hydraulic fluid for a steering system. In the second state, the inlet of the first reversing valve communicates with both the first outlet and a second outlet of the first reversing valve, so that the pressure control valve controls the pressure of the hydraulic fluid output to the steering system through the first outlet of the first reversing valve. Through application of the technical scheme of the vehicle hydraulic system and the engineering vehicle, the problems that in the prior art, a steering wheel is too sensitive during high-speed rotation of an engine, and steering assistance force is small during low-speed rotation of the engine are solved.