An engine starter device for vehicles comprising: a generator/starter that is connected to a crankshaft of an engine and rotates synchronously with the crankshaft; and a kick starter that kick-starts the engine, and a means for igniting the engine, and a rotor sensor for detecting at least one permanent magnet mounted on an inner rotor of the generator/starter; an engine control unit which comprises: a motor stage identification means for identifying a motor stage representing a rotational angle of the generator/starter based on the rotor sensor signal; and a reverse rotation detection unit for determining whether or not the engine rotates reversely on the basis of the change in the motor stage; and a means for measuring, when the forward rotation has been detected, the time (Δt) required by the engine to pass the motor stage, which is preceding the motor stage, which comprises a compression top dead center; the engine starter device being characterized in that the engine control unit further comprises: an ignition prohibition means that permits the ignition of the engine, when the measured time is less than a kickback determination threshold (Δt ref) and that prohibits the ignition when the measured time is equal or more than the kickback determination threshold (Δt ref). a generator/starter that is connected to a crankshaft of an engine and rotates synchronously with the crankshaft; and a kick starter that kick-starts the engine, and a means for igniting the engine, and a rotor sensor for detecting at least one permanent magnet mounted on an inner rotor of the generator/starter; an engine control unit which comprises: a motor stage identification means for identifying a motor stage representing a rotational angle of the generator/starter based on the rotor sensor signal; and a reverse rotation detection unit for determining whether or not the engine rotates reversely on the basis of the change in the motor stage; and a means for measuring, when the forward rotation has been detected, the time (Δt) required by the engine to pass the motor stage, which is preceding the motor stage, which comprises a compression top dead center; the engine starter device being characterized in that the engine control unit further comprises: an ignition prohibition means that permits the ignition of the engine, when the measured time is less than a kickback determination threshold (Δt ref) and that prohibits the ignition when the measured time is equal or more than the kickback determination threshold (Δt ref). a motor stage identification means for identifying a motor stage representing a rotational angle of the generator/starter based on the rotor sensor signal; and a reverse rotation detection unit for determining whether or not the engine rotates reversely on the basis of the change in the motor stage; and a means for measuring, when the forward rotation has been detected, the time (Δt) required by the engine to pass the motor stage, which is preceding the motor stage, which comprises a compression top dead center; the engine starter device being characterized in that the engine control unit further comprises: an ignition prohibition means that permits the ignition of the engine, when the measured time is less than a kickback determination threshold (Δt ref) and that prohibits the ignition when the measured time is equal or more than the kickback determination threshold (Δt ref).