Method for controlling a diesel engine provided with a common-rail injection system, a DeNOx oxidizing catalyser and a particulate filter arranged downstream of said DeNOx oxidizing catalyser, comprising the steps of: - performing at least one main fuel injection (PRE, MAIN) into a cylinder of said engine, the injected fuel being intended to take part in a combustion inside said cylinder, and - performing a fuel post-injection (POST) in order to inject a total quantity of fuel (QPOST) inside said cylinder, said fuel post-injection being so separated from said main fuel injection (PRE, MAIN) that the fuel injected during said fuel post-injection does not take part in said combustion and reaches said DeNOx oxidizing catalyser at least in part in an unburned state in order to cause an exothermic reaction in said DeNOx oxidizing catalyser; said method further comprising the step of performing an auxiliary fuel injection (AFTER) after and so close to said main fuel injection (PRE, MAIN) as to combust inside said cylinder, characterized by comprising the step of dividing said fuel post-injection (POST) into a plurality of separate fuel post-injections (POST1, POST2, POST3), and in that the timing and quantity of said auxiliary fuel injection (AFTER) is such as to cause a first increase in the temperature of the exhaust gases reaching said DeNOx oxidizing catalyser, and the quantity and timing of said fuel post-injection (POST) is such as to cause a second increase in the temperature of said exhaust gases, the combination of said first and second increases determining a target temperature of said exhaust gases at the inlet of said particulate filter, such as to cause regeneration thereof. - performing at least one main fuel injection (PRE, MAIN) into a cylinder of said engine, the injected fuel being intended to take part in a combustion inside said cylinder, and - performing a fuel post-injection (POST) in order to inject a total quantity of fuel (QPOST) inside said cylinder, said fuel post-injection being so separated from said main fuel injection (PRE, MAIN) that the fuel injected during said fuel post-injection does not take part in said combustion and reaches said DeNOx oxidizing catalyser at least in part in an unburned state in order to cause an exothermic reaction in said DeNOx oxidizing catalyser; said method further comprising the step of performing an auxiliary fuel injection (AFTER) after and so close to said main fuel injection (PRE, MAIN) as to combust inside said cylinder, characterized by comprising the step of dividing said fuel post-injection (POST) into a plurality of separate fuel post-injections (POST1, POST2, POST3), and in that the timing and quantity of said auxiliary fuel injection (AFTER) is such as to cause a first increase in the temperature of the exhaust gases reaching said DeNOx oxidizing catalyser, and the quantity and timing of said fuel post-injection (POST) is such as to cause a second increase in the temperature of said exhaust gases, the combination of said first and second increases determining a target temperature of said exhaust gases at the inlet of said particulate filter, such as to cause regeneration thereof.