In order to lower the reliance on single controller in Software Defined Optical Network (SDON), avoid the conflict of different controllers, and improve effectively the survivability on the control plane, the survivable design of SDON control plane based on minimum point covering is proposed. Combined with the constraint of centralized control, the algorithm based on the minimum point covering establishes reliable hierarchical control model, and sets control priority to controllers. The master controller with the highest priority centralized controls the whole net, and the next comes the regional controller, which only intensively controls regional traffic, besides the authority switch which is introduced to control local wavelength in the optical layer owns the lowest level. Meanwhile, the model based on cross-layer information designs survivability redundancy for routing and allocates resource for the control channel. Simulation results show that the proposed strategy can satisfy the request on control delays, and lower the failure probability in the control plane by 30%, thus promoting the network survivability under critical environment.