To reduce erroneous detection in misfire determination based on rotational fluctuation of an engine.

In a control device for an internal combustion engine determining whether the misfire is caused or not from fluctuation of the rotational speed of the internal combustion engine, a determination value compared to the rotational speed when EGR is performed by operating an EGR device attached to the internal combustion engine is learnt and updated based on the rotational speed repeatedly measured during EGR and the distribution of occurrence frequency thereof.