A system for exhaust gas purification comprising, in the following order from an upstream side of an exhaust passage of an internal combustion engine: a device for direct injection into an exhaust pipe; an oxidation catalyst; and at least one of a catalyst for NOx removal and a catalyzed DPF, characterized in that a support of the oxidation catalyst is formed of a metallic material or a material having a specific heat not higher than that of a metallic material into a structure having a function of mixing exhaust gas, characterized in that the system further comprises an exhaust gas purification control unit which is adapted to perform: in-exhaust pipe direct injection in a predetermined first supply amount for raising a temperature of the oxidation catalyst when a first index temperature (Tc) indicative of a temperature of the oxidation catalyst is above a first judgment temperature; in-exhaust pipe direct injection in a predetermined second supply amount for raising a temperature of the exhaust gas when the first index temperature (Tc) is above a second judgment temperature; and in-exhaust pipe direct injection in a predetermined third supply amount for performing a corresponding one of regeneration by NOx removal and forced regeneration by PM removal when a second index temperature (Tn) indicative of a temperature of the at least one of the NOx occlusion/reduction type catalyst and the catalyzed DPF rcaches a third judgment temperature (Tn3, Tp3). a device for direct injection into an exhaust pipe; an oxidation catalyst; and at least one of a catalyst for NOx removal and a catalyzed DPF, characterized in that a support of the oxidation catalyst is formed of a metallic material or a material having a specific heat not higher than that of a metallic material into a structure having a function of mixing exhaust gas, characterized in that the system further comprises an exhaust gas purification control unit which is adapted to perform: in-exhaust pipe direct injection in a predetermined first supply amount for raising a temperature of the oxidation catalyst when a first index temperature (Tc) indicative of a temperature of the oxidation catalyst is above a first judgment temperature; in-exhaust pipe direct injection in a predetermined second supply amount for raising a temperature of the exhaust gas when the first index temperature (Tc) is above a second judgment temperature; and in-exhaust pipe direct injection in a predetermined third supply amount for performing a corresponding one of regeneration by NOx removal and forced regeneration by PM removal when a second index temperature (Tn) indicative of a temperature of the at least one of the NOx occlusion/reduction type catalyst and the catalyzed DPF rcaches a third judgment temperature (Tn3, Tp3). in-exhaust pipe direct injection in a predetermined first supply amount for raising a temperature of the oxidation catalyst when a first index temperature (Tc) indicative of a temperature of the oxidation catalyst is above a first judgment temperature; in-exhaust pipe direct injection in a predetermined second supply amount for raising a temperature of the exhaust gas when the first index temperature (Tc) is above a second judgment temperature; and in-exhaust pipe direct injection in a predetermined third supply amount for performing a corresponding one of regeneration by NOx removal and forced regeneration by PM removal when a second index temperature (Tn) indicative of a temperature of the at least one of the NOx occlusion/reduction type catalyst and the catalyzed DPF rcaches a third judgment temperature (Tn3, Tp3).