To prevent an engine from deteriorating combustion of the engine which is in unstable state of the combustion just after fuel supply is restarted.

A control device of the engine is provided with an exhausting reflux passage (25) in fluid communication with an intake passage (13) and a first cylinder group exhaust passage (23A) into which only exhaust of a first cylinder group flows, an exhausting reflux control valve (26) and a fuel cut means (31) which stops supplying the fuel in the all cylinders when fuel cut condition is satisfied. The control device of the engine is provided with an opened valve commanded means (31) which commands to open the valve with respect to an exhausting reflux control valve (26) when the fuel cut condition is similarly satisfied, a closed valve commanded means (31) which commands to close the valve with respect to the exhausting reflux control valve (26) when condition which restarts to supply the fuel is satisfied after fuel supply of all the cylinders is stopped. It is also provided with a cylinder classified fuel supply restart means (31) which restarts to supply the fuel of a second cylinder group when condition which restarts to supply the fuel is similarly satisfied and restarts to supply the fuel of the first cylinder group by providing time delay behind restart of the fuel supply.