Top structure of direct-injection gasoline engine piston

The invention discloses a top structure of a direct-injection gasoline engine piston. The top structure of the direct-injection gasoline engine piston comprises a horseshoe-shaped protrusion arranged on the top of the piston. An approximately basin-shaped pit is enclosed in the protrusion and is closer to the left of the piston relative to the top center of the piston. The bottom surface of the pit is a flat surface inclined downwards from left to right. The right of the protrusion is provided with an exhaust opening inclined downwards for avoiding the inclined surface. The top structure of the direct-injection gasoline engine piston can increase the compression ratio of engine combustion and improve the engine thermal efficiency and the fuel economy.