The invention provides an underwater wireless multi-hop network initialization method. The method comprises the steps that a master control node broadcasts hello packets and informs all nodes in a network of starting initializing; first to m-hop nodes add locally obtained newest neighbor information to the hello packets in sequence and send the hell packets to the network; m-1 to first-hop nodes add local topology information to partial topology information and send the partial topology information to the network; and after the master control node obtains whole network topology information, the first to m-hop nodes send the whole network topology information to the network in sequence. According to the method, the topology discovery can be finished by the whole network nodes with low cost and low energy consumption, and a consistent whole network topology is obtained.