An exhaust gas recirculating device in which the intake mixed fuel gas passageway is surrounded by a double wall tube which defines a ring shaped space therebetween. Recirculating exhaust gas is introduced into the ring shaped space to heat the inner tube of the double wall to ease vaporization of the wall stream of fuel and the exhaust gas is blown out from a narrowed outlet of the space so as to well mix the fuel gas mixture and the recirculating exhaust gas.