An engine controller capable of reducing torque fluctuation and the like in change between spark ignition combustion and homogeneous charge compression ignition combustion is provided. Spark ignition burning mode or homogeneous charge compression ignition burning mode is selectively set as burning mode according to the operating state of an engine. In spark ignition burning mode, a spark plug is used. In homogeneous charge compression ignition burning mode, fuel is burned utilizing pressure rise in a combustion chamber in conjunction with the ascent of a piston. The burning mode is changed between these modes. In transition for change between the spark ignition burning mode and the homogeneous charge compression ignition burning mode, the following measure is taken: a period during which the lift amount and/or the valve opening period (IVevent) of an intake valve is made smaller than a set value for the homogeneous charge compression ignition burning mode is provided.