Aiming at the characteristics of long delay, high error code, high dynamoic and asymmetric propagation of uplink and downlink in space-ground integrated data link, an integrated data link slot synchronization method based on moving nodes is proposed. By using the numbering in the asking messages and response messages, the time required for each message transmission is determined, and the synchronization can be completed in different slots to improve the utilization efficiency of the time resource. Aiming at the high-speed motion of nodes, a change rule of propagation delay is assumed, which is calculated by increasing the number of message transmission times. Then, the slot deviation caused by node motion is calculated and the deviation is compensated and the synchronization accuracy and stability is improved. The simulation results show that the integrated data link slot synchronization algorithm improves the synchronization accuracy under the premise of completing the integrated data link synchronization.