In this paper, we proposes a cascading failure model for the complex network with hierarchy structure which is common in real networks. This model can be used to optimize the financial or logistic network design. The hierarchy network has a tree-shape backbone and many random hidden linkages. The branches of each node in the backbone follow normal distribution. The attack on the network is from bottom layer under the condition of incomplete information, i.e., on the assumption that the attacker cannot observe the hidden linkages. The load redistribution of the failure nodes takes into consideration the hierarchy heterogeneity, of which the network tends to redistribute extra load to intact nodes of the same or higher hierarchies. Simulation experiment shows that the topology of hierarchy network changes from small world network into random network with the variation of linkage parameters. The size of cascading failure firstly increases and then decreases with the hidden linkage ratio increasing and the network shows higher robustness when the load of failure node is redistributed to the intact node with high hierarchy. The experiments also demonstrate that the linkage parameters play a significant role in the robustness of the network because these parameters can affect the hierarchy distribution of hidden links. Therefore, in order to achieve better robustness of network, we should reasonably choose parameters in topology design and network control strategies.