The invention provides a two-
stroke engine. A
piston is arranged between two air cylinder guide rails,
piston grooves are formed in the air cylinder guide rails, and the
piston slides along the air cylinder guide rails. An air cylinder is arranged in the piston and fixed to the air cylinder guide rails through openings of the piston grooves, and the air cylinder is matched with the air cylinder guide rails to divide an inner cavity of the piston into two independently sealed air chambers; the two opposite sides, located on the two air chambers, of the air cylinder are respectively provided with a groove, an air
inlet channel, an ignition placement channel, an air
inlet valve placement channel, an air exhaust channel and an
exhaust valve placement channel are arranged between the side walls of the grooves and the air cylinder guide rails, an air
inlet valve is arranged in the air
inlet valve placement channel, an ignition device is arranged in the ignition placement channel, and an
exhaust valve is arranged in the
exhaust valve placement channel. The power of the working volume of the air cylinder is higher, air inlet is full, exhaust is complete, and fuel is saved; ignition efficiency is high, the spreading speed of sparks is high, lubricating and cooling are easier to conduct,
machine oil consumption is small, mechanical loads and thermal loads are small, and the service life of the engine is longer.