A muffling apparatus 1 of the present invention having an exhaust emission purifying function, including a turning portion 8 in an inside of an exhaust gas flow passage, and having an injection nozzle 12 disposed in an upstream side exhaust gas flow passage 9 of the turning portion 8, for injection-supplying a liquid reducing agent; and a reduction catalytic converter 13 disposed in a downstream side exhaust gas flow passage 10 of the turning portion 8, for reductively purifying nitrogen oxides with the liquid reducing agent. The apparatus further includes a diffusing member 15, which generates a vortex flow of a gas traveling in a vertical plane of the turning portion 8 to diffuse the liquid reducing agent.