The invention discloses a method for predicting the reliability of a communication network, which can predict the reliability of the network. The method comprises the following steps of: modeling the reliability of the communication network; enumerating all minimum cuts between any two nodes of the communication network; enumerating a network minimum cut subset from each minimum cut; writing a network reliability expression by utilizing SDP technology; and substituting link unreliability into the network reliability expression to solve the network reliability.