The embodiment of the invention provides a data transmission method based on a satellite optical burst system. The system comprises at least two edge satellites and at least one core satellite. The first edge satellite gathers to-be-transmitted data into a burst control packet and a burst data packet, and sends the burst control packet and the burst data packet to the first core satellite. The first core satellite performs routing calculation and spectrum allocation, and sends a calculation result, a burst control packet and a burst data packet to the next core satellite. When the middle coresatellite is not the second core satellite, the received various types of information are sent to the next core satellite. When the intermediate core satellite is a second core satellite, the burst control packet and the burst data packet is sent to a second edge satellite. The second edge satellite unpacks the burst control packet and the burst data packet into to-be-transmitted data and sends the to-be-transmitted data to the destination node. Compared with the prior art, by applying the scheme provided by the embodiment of the invention, the waste of spectrum resources can be reduced, and the spectrum utilization rate is improved.