Engine ventilation system

The invention discloses an engine ventilation system. The engine ventilation system is provided with an oil-gas separator, an oil return pipe, a ventilation pipe and an oil suction pump, wherein the ventilation system comprises a crankcase, the oil suction pump, an oil pan oil collection area, integrated oil tanks, a cylinder head cover and a first oil-gas channel; the oil suction pump is arrangedin an oil pan of an engine and used for sucking engine oil from the oil pan; the oil pan oil collecting area is positioned at the lower part of the crankcase; the integrated oil tanks are positionedon two sides of the crankcase upper part; the cylinder head cover is arranged on a cylinder head; the first oil-gas channel communicates between the cylinder head cover and the top of the integrated oil tanks; and when the oil suction pump sucks engine oil from the oil pan oil collection area to the integrated oil tanks, a part of oil gas is sucked into the integrated oil tanks at the same time, so that the oil gas pressur