Abstract: An engine igniting coil device adapted to be mounted in a cylindrical bore of an engine and directly connected with an ignition plug therein has a coil case containing an igniting coil assembly and made of conductive magnetic material which is held at the ground potential level, thus preventing a decrease of output factor of the igniting coil of produced magnetic flux when spreading about and passing through a cylinder head of the engine and eliminating the possibility of leakage discharge from a high-voltage portion of the igniting coil assembly to the coil case and the cylinder head.