The invention discloses a communication method and system for an airborne broadband communication system. The method comprises the following steps: step A, simulating the behavior logic of opposite terminal equipment and maintaining continuous communication, and acquiring data and physical layer information in a first subnet; step B, reading the physical layer information and extracting the data,mapping the data into a protocol layer, and packing the data; step C, extracting protocol layer information, and selecting a corresponding communication system to send a data packet; and step D, receiving the data packet, and restoring the data packet into a bus data packet in the first subnet and sending the bus data packet to a second subnet according to the reverse processing of steps A to C. The method improves the timeliness and traceability of data acquisition, and can significantly enhance the operating efficiency of airline companies.