The present invention relates to an access control method and device of an unmanned store. The method comprises the steps of: receiving an out-of-store door opening request signal; if a magneto-acoustic marker of a commodity corresponding to the out-of-store door opening request signal is magnetic, determining whether a user has paid an order; and if yes, unlocking the access control. The access control method and device of the unmanned store can determine whether the user has paid the order or not in a condition that the degaussing of the magneto-acoustic marker attached on the pack of the paid commodity is failed to determine unlocking or locking of access control so as to ensure the unlocking of the access control when the paid commodity is taken out of the store and effectively improvethe user experience of self-service purchase through locking of the access control when non-paid commodity is taken out of the store.