A hook device having a hook body, a stopper for preventing the hook body from slipping off a member to be connected, an elastic member for biasing the stopper toward a slipping-off preventing position, and a connecting pin for connecting these components together. The stopper is formed with a slot having the connecting pin inserted therethrough. The slot has a stopper guide portion for permitting the stopper to move between the slipping-off preventing position and a slipping-off permitting position, and a stopper lock portion allowing the connecting pin to fit in when the stopper is further moved from the slipping-off permitting position. The hook device further has a stopper returning mechanism for moving a stopper unlocking knob portion toward the slipping-off preventing position.