An ignition device for an internal combustion engine is provided which improves ignition while reducing electric power consumption. An ignition device for an internal combustion engine includes an ignition plug that is placed with a tip exposed on an end in an axial direction of a combustion chamber formed in a cylinder and that includes a central electrode and a grounding electrode provided opposing each other at the tip, and a magnetic field former that forms a magnetic field in a direction in which a magnetic field vector substantially vertically passes through an approximate two-dimensional plane including a spark discharge path formed, by a gas flow ejected to the end in the axial direction of the combustion chamber, between the central electrode and the grounding electrode, and extending in an approximate U shape in a direction orthogonal to the opposing direction of the electrodes.