A control device of an internal combustion engine, which is adapted to control the internal combustion engine performing lean burn and comprising plural cylinders and an exhaust system, the exhaust system comprising: first exhaust valves (7a1, 7b1, 7c1, 7d1) and second exhaust valves (7a2, 7b2, 7c2, 7d2) provided in each of the plural cylinders; a first exhaust passage communicating with the first exhaust valves (7a1, 7b1, 7c1, 7d1); a second exhaust passage communicating with the second exhaust valves (7a2, 7b2, 7c2, 7d2); a first exhaust gas purifying catalyst (10a, 10b) provided at least on one of the first exhaust passage and the second exhaust passage; and a second exhaust gas purifying catalyst provided on an exhaust passage downstream of a junction of the first exhaust passage and the second exhaust passage, characterized in that the control device comprises a control means which is adapted to control each of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2) independently, wherein the control means is adapted to perform a S-poisoning regeneration control in which the control means is adapted to make a part of the plural cylinders perform stoichiometric combustion or rich combustion and make remainder of the plural cylinders perform lean combustion, and wherein the control means is adapted to stop one of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2) provided in each of the plural cylinders and operate the other of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2), at a time of the S-poisoning regeneration control, such that only one of exhaust gas from the cylinder performing the stoichiometric combustion or the rich combustion and exhaust gas from the cylinder performing the lean combustion flows into the first exhaust gas purifying catalyst (10a, 10b). first exhaust valves (7a1, 7b1, 7c1, 7d1) and second exhaust valves (7a2, 7b2, 7c2, 7d2) provided in each of the plural cylinders; a first exhaust passage communicating with the first exhaust valves (7a1, 7b1, 7c1, 7d1); a second exhaust passage communicating with the second exhaust valves (7a2, 7b2, 7c2, 7d2); a first exhaust gas purifying catalyst (10a, 10b) provided at least on one of the first exhaust passage and the second exhaust passage; and a second exhaust gas purifying catalyst provided on an exhaust passage downstream of a junction of the first exhaust passage and the second exhaust passage, characterized in that the control device comprises a control means which is adapted to control each of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2) independently, wherein the control means is adapted to perform a S-poisoning regeneration control in which the control means is adapted to make a part of the plural cylinders perform stoichiometric combustion or rich combustion and make remainder of the plural cylinders perform lean combustion, and wherein the control means is adapted to stop one of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2) provided in each of the plural cylinders and operate the other of the first exhaust valves (7a1, 7b1, 7c1, 7d1) and the second exhaust valves (7a2, 7b2, 7c2, 7d2), at a time of the S-poisoning regeneration control, such that only one of exhaust gas from the cylinder performing the stoichiometric combustion or the rich combustion and exhaust gas from the cylinder performing the lean combustion flows into the first exhaust gas purifying catalyst (10a, 10b).