A combustion apparatus including a mixture feeding pipe for injecting a mixture of pulverized coal and combustion air into a furnace, with the mixture then being ignited. A radially outwardly flared flame maintaining ring is provided at a tip end of the mixture feeding pipe, with the maintaining ring being exposed to a reduced atmosphere and to high temperatures due to radiant heat from the furnace. A projection extends into the furnace beyond the flame maintaining ring so as to protect the flame maintaining ring from radiation from inside the furnace thereby suppressing an excessive increase in temperature. Combustion air flows along a surface of the projection so as to provide at oxidized atmosphere. A pulverized coal/air separating member extends within the mixture feeding pipe, and a portion or separation of the flow forcibly occurs is locally formed in a conical end portion of the pulverized coal/air separating member, whereby it is possible to effect a complete combustion in a stabilized manner regardless of the unit capacity and load of the combustion apparatus.