Electronic key device for vehicle and starting control method for vehicle

An electronic key device for a vehicle which performs starting of the vehicle by performing ID verification against a portable electronic key unit includes an ID verification device which performs ID verification against the portable electronic key unit when pushing in operation of an ignition knob has been performed, a decision device which decides whether or not the portable electronic key unit is present within the vehicle when vehicle starting operation has been performed, and a vehicle starting control device which performs starting control of the vehicle, when the ID checking result and also the result of the decision by the decision device are both affirmative. When the number of times that the result of ID checking is negative and also it is decided that the portable key unit is not present within the vehicle arrives at a predetermined value, a locked mode is set in which thereafter starting of the vehicle is prohibited unless a predetermined procedure is performed. On the other hand, when the result of ID checking is affirmative and also it is decided that the portable key unit is not present within the vehicle, then no such predetermined number of times calculation for setting the locked mode is performed.