In the ignition device for the battery-less engine, a transistor-type ignition control circuit of the engine including a manual starting device is actuated by using output of the generator driven by the engine, and a primary winding of an ignition coil is powered from the ignition control circuit. In the ignition control circuit, a primary powering time period for powering the primary winding from the ignition control circuit is set shorter than a predetermined time period while an engine speed of the engine is within a low engine speed range below a predetermined engine speed, whereas the primary powering time period is set equal to or longer than the predetermined time period while the engine speed of the engine is within a high engine speed range at and above the predetermined engine speed.