PURPOSE: To completely prevent half-latching condition as well as raise the operability of an unlocking device by a method in which when half-latching condition and a recovery action are detected by a door opening and closing detecting switch and a steering wheel detection switch, unlocking action is made possible.

CONSTITUTION: A control circuit is made up of a steering wheel detecting switch 9, a locking and unlocking detecting switch 10, a door opening and closing detecting switch 11, AND circuits 12, 13, and 14, and a monostable multivibrator 15. When detecting half-latching condition by the switch 11 and also detecting locking condition by the switch 10, an outside handle provided to the outside of door is unlocked for recovery action, whereupon the action is detected by the switch 9 and the actuator does unlocking action to make the locking and unlocking mechanism a release state. Afterwards, the outside handle is unlocked to open the door.