Abstract: An internal combustion engine, especially of a two-stroke engine in a portable handheld work apparatus, includes an outlet (27) for the exhaust gases which is fluidly connected with at least one inlet opening (13, 14) in an exhaust-gas muffler (1). At least one resonance pipe (6, 7) is mounted in flow direction between the outlet (27) from the engine (20) and the inlet opening (3, 5) into the exhaust-gas muffler (1) in order to obtain a good noise attenuating result and simultaneously make possible an advantageous, space-saving mounting of the engine (20).