To provide an ignition coil mounting structure reducing friction at a time of turning an ignition coil when the ignition coil is turned to lock a locking part with a locked part after inserting a coil part of the ignition coil into a coil insertion hole of a cylinder head.

In this mounting structure, the ignition coil 20 composed of a pole shape coil part 21 and a control part 24 connected to one end of the coil part is mounted by seating the control part on a end surface 11 of a cylinder head 10 and inserting the coil part into the coil insertion hole 12 opening on the end surface. The structure consists of the locking part 15 formed on the cylinder head 10 or the ignition coil, the locked part 27 formed on the ignition coil or the engine head and locked with the locking part by turning the ignition coil, and friction reducing means 36, 38 reducing friction between the ignition coil and a cylinder head at a time of turning the ignition coil.