The present invention provides a high speed data management and transmission system and method for a micro satellite. The system comprises an integrated digital unit which comprises a DSP chip and an FPGA chip and is installed in the integrated electronic chamber of the micro satellite in the form of an insertion plate and communicates with the integrated electronic chamber through a mounting interface, a storage array which is used for storing the high speed data flow and real-time data flow written by the FPGA chip, and an X frequency band modulator which is used for modulating the base band signal formed by the FPGA chip in carrying out a multiple-connection operation and sends an X frequency band RF signal to the ground through an X frequency band antenna. According to the system and the method, high speed data management equipment and data transmission equipment are integrated, and the system has the advantages of small size, light weight and low power consumption and has an important meaning for a micro satellite with the strict restriction on layout and power consumption. According to a digital part integrated design, the interface between equipment is saved, and the overall satellite assembly layout is facilitated.