The invention provides an appointment service system for shared parking stalls. A mobile terminal of a user applies for an electronic key for an intelligent electric-control parking stall ground lock of certain shared parking stall; a secret key management server establishes an unlocking pairing relation between user identification information of the user mobile terminal and parking stall identification information of the corresponding intelligent electric-control parking stall ground lock; according to the unlocking pairing relation, the electronic key of the corresponding intelligent electric-control parking stall ground lock is generated and returned to the user mobile terminal; and the electronic key is used to unlock the intelligent electric-control parking stall ground lock. Namely, the right of using the shared parking stall is handed over remotely, the electronic key is used for unlocking to identify and verify individual difference among users, remote handover of the right of using the shared parking stall is highly exclusive safe, the shared parking stalls can be used temporarily and rapidly, and the technical problem in applying and popularizing vacant parking stall resource can be solved.