Exhaust emission control device of internal combustion engine

This invention has: NOx catalyst 17, it set Yu can dilute burning of internal combustion engine exhaust channel within, can release out and through restore agent absorption NOx; restore agent supply device 19, it set in NOx catalyst 17 upstream side Shang of exhaust channel in the; load detection device, it for determination internal combustion engine 1 of load; and restore agent added control device, it according to internal combustion engine 1 of load control restore agent of added time and added interval, Also takes into account the reducing agent in this control by engine 1 exhaust gas velocity and temperature of glued to the inner surface of the exhaust channel level, so that I can have nothing to do with operating conditions to restore a full dose supply to NOx catalyst. In this way, even if the internal combustion engine operating conditions change, always supply the right amount of NOx catalyst reducing agent.