Abstract: In view of the characteristics of decentralized, distributed and highly dynamic in space-ground integration networks（SGIN）, a dispersed computing-dependent routing（DCDR）control strategies considering computing mapping and dynamic distribution is proposed. By building the user service as a directed acyclic graph（DAG）model, an improved directional diffusion algorithm（IDDA）is designed to find a solution and to realize the task of transmitting and computing while making mapping strategy in SGIN, and the computing is mapped to an end-to-end transmitting path. The simulation results show that this algorithm can complete transmitting and computing efficiently, with better invulnerability.