With the rapid advancement of remote sensing satellite technology in China, space missions are becoming increasingly complex, posing challenges to traditional spaceborne storage and data transmission systems in terms of high customization and costly migration. This study aims to develop an integrated high-performance storage and data transmission system to address these issues. Leveraging the high flexibility of field-programmable gate arrays (FPGAs), the system design incorporates SATA III solid-state drive read/write access with a file system, multi-channel DDR controllers with data multiplexing control, and data transmission functionality supporting intermediate frequency modulation.With minimal device and software deployment, the system achieves a maximum downlink bandwidth of 900 Megabits per second and offers the most diverse data transmission capabilities. The system has been successfully implemented in a specific Jitian satellite model mission. Ground tests demonstrate that the payload storage link bandwidth remains consistently stable above 2.8 Gigabits per second, with peak bandwidth reaching 3.69 Gigabits per second. Both storage and data transmission operations achieve long-term zero-error code performance. On-orbit verification confirms clear and complete transmission of payload images. The system fully meets the stringent stability and reliability requirements of remote sensing satellites, demonstrating significant application value in the field of remote sensing satellite technology.