In order to attain robust fault allocation and restoration in the case of uncertain fault diagnosis of distribution grids, the fault information received is blended with other related information, based on which, the fault probability of each distribution area is evaluated using the Bayes approach. A hierarchical model for distribution grids is developed and the steps of restoration are worked out in accordance with the fault probabilities and the hierarchy of the distribution areas. The refused actions of switches are considered as well. Two examples are given to illustrate the proposed approaches. It is shown that meaningful fault allocation is achieved even in the case of misreporting or failed-report of fault information. The proposed restoration approach is feasible for both radial and looped distribution grids.