In order to achieve the deterministic transmission of diverse data streams in a short time on the SpaceFibre network, the fine-grained low-latency deterministic scheduling algorithm with classification was proposed. According to the differentiated scheduling strategy, space tasks were divided into three types. For the efficient allocation of resources, the extended time-slot was introduced. The uniform distribution of time-slot without conflict reduced the average delay of data packets. To adapt to aerospace applications where payloads were connected with a network, the method generated scheduling vectors based on the network topology. The simulation model of the SpaceFibre network in OPNET was built to verify the effectiveness of the method. Experimental results show that the scheduling scheme generated by the method has better certainty than the classic scheduling based on priority and conflict-free consecutive scheduling; with the increment of the number of time slots, the average delay and jitter of each traffic are reduced, and the throughput is guaranteed. Therefore, the method has certain practical application value in aerospace engineering.