A spark arrester includes a buffer plate against which exhaust gases discharged from the outlet end of a tail pipe strike directly. Upon impingement on the buffer plate, the exhaust gases become turbulent or agitated whereupon temperature distribution of the exhaust gases is made uniform. The buffer plate has a plurality of through-holes arranged to allow passage of the exhaust gases after the exhaust gases impinge against the buffer plate. After passing through the through-holes, the exhaust gases flow through a wire screen during which time sparks in the exhaust gases are caught by the wire screen. The exhaust gases are then guided downstream along a guide tube and finally released from an outlet end of the guide tube. A stream of exhaust gases discharged from the guide tube has only a limited length of high-temperature zone.