The invention provides a reliable mobile RPL routing method based on link energy saving, and belongs to the technical field of wireless sensor network communication. The whole communication process is divided into three stages: a detection and transmission stage, a reaction and prediction stage and an announcement stage. The method comprises the following three innovative mechanisms: modifying a control message frame format, selecting a father node by combining priorities, and setting a reachable timer; modifying a control message frame format in combination with different interaction scenes, so the backward compatibility of a control message is ensured, and meanwhile, the additional overhead caused by adding an additional control message is avoided; based on multiple metric values and in combination with priority selection PPN, considering the network depth and the upstream link energy of the alternative father node, so the energy consumption of part of SN can be avoided, and the survival time of the whole network is effectively prolonged; and finally, enabling a part of CPNs to start a reachable timer after receiving the DAO, and considering the condition of forwarding the DAO or DAO-ACK loss, so the link construction failure caused by the loss of the control message is effectively avoided, and the transmission efficiency can be improved.