A two-stroke combustion engine with intake and exhaust ports which are indirectly or directly controllable in accordance with the reciprocating motion of a working piston in a cylinder space, wherein at one side of the piston there is a working chamber accessible to an ignition device and connectible to an outlet, and at the other side of the piston there is a compression chamber, and wherein there is associated with the working piston at least a second auxiliary piston functioning as a compression piston, which operates in a compression chamber at least in a single acting mode.