The invention discloses a service reliability and bandwidth recovery method based on multiple channels, and belongs to the technical field of communication networks. According to the method, for serious damage and threat of large-scale disaster events to the backbone optical network, a flexible routing configuration and bandwidth supplementing method is adopted to recover damaged services in the network. The objective of the invention is to deal with post-disaster network resource shortage and network component reliability reduction. Routes and number of recovery channels are dynamically adjusted according to service reliability requirements, bandwidths are evenly distributed and adaptively upgraded according to service bandwidth requirements, and the routes and the bandwidths are furthersupplemented for damaged services according to a resource utilization rate maximization principle, so that the performance aspects of service interruption rate, reliability, bandwidth loss rate and the like are greatly improved.