Aiming at the less flexibility and efficiency of the current access selection algorithm,a parallel-queuing-based dynamic online selection algorithm for th e future space-based optical satellite network is studied.The constraints of access sel ection are analyzed and a mathematical model is established.Based on the queuing model,a dynamic pri ority strategy is introduced to achieve different services for different priority tasks.Time sens itivity factor is brought in to adjust partition degree of the delay for different priority tas ks,which can avoid all-the-time preemption of the lower priority task.The parallel queuing strat egy is proposed to get shorter waiting time,optimizing the scheduling solution globally.Simula tion results show that the proposed algorithm can shorten the time delay by about 30%,which promo tes the flexibility and efficiency significantly.